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71.
A new series of DNA binding 5,10,15-tri(N-methyl-4-pyridiniumyl)porphyrin (TrisMPyP)-platinum(II) conjugates was synthesized, in which different spacer ligands were used for appropriate coordination to platinum(II) complexes. Compound 9b exhibited in vivo antitumor activity (T/C%, 294) superior to cisplatin (T/C%, 184) against the leukemia L1210 cell line. 相似文献
72.
A novel dual stage chemiluminescence detection system incorporating individually controlled hot stages has been developed and applied to probe for material interaction effects during polymer degradation. Utilization of this system has resulted in experimental confirmation for the first time that in an oxidizing environment a degrading polymer A (in this case polypropylene, PP) is capable of infecting a different polymer B (in this case polybutadiene, HTPB) over a relatively large distance. In the presence of the infectious degrading polymer A, the thermal degradation of polymer B is observed over a significantly shorter time period. Consistent with infectious volatiles from material A initiating the degradation process in material B it was demonstrated that traces (micrograms) of a thermally sensitive peroxide in the vicinity of PP could induce degradation remotely. This observation documents cross-infectious phenomena between different polymers and has major consequences for polymer interactions, understanding fundamental degradation processes and long-term aging effects under combined material exposures. 相似文献
73.
This review aims to provide a summary of the progress in organic small molecular fluorescent dyes for photodynamic therapy in recent years and it is classified according to the structures of dyes including cyanines, phthalocyanine, BODIPYs and other agents. 相似文献
74.
介绍了对尿汞快速测定法的改进,用消泡剂磷三丁酸消除尿中泡沫,并讨论了尿汞测定的最佳条件,本法的相对标准偏差为4.8-9.0%,回收率94-101%。 相似文献
75.
76.
赖氨酸-Ag反应机理的研究 总被引:5,自引:0,他引:5
The interaction of silver(Ⅰ) ion with lysine has been investigated by UV-Vis, fluorescent spectra and electrophoresis method. The effect of pH medium and multicomponent concentration on interaction of lysine-silver has also been studied. Lysine-silver system showed maximum absorbance at 239 nm and 448 nm. Lysine showed fluorescence. The fluorescence excitation wavelength was about 356.6 nm (fluorescence emission wavelength was about 438.6 nm). When the reaction of silver(Ⅰ) ion with lysine happened, fluorescence was quenching. Lysine-silver system carried negative charge, and the electrokinetic potential of double electrode layer was -2.35×10-4 V. 相似文献
77.
78.
The effect of calcining conditions on the rehydration of dead burnt magnesium oxide using magnesium acetate as a hydrating agent 总被引:1,自引:0,他引:1
C. A. Strydom E. M. van der Merwe M. E. Aphane 《Journal of Thermal Analysis and Calorimetry》2005,80(3):659-662
Summary Magnesium oxide was produced through calcination of magnesite ore. A rehydration percentage of MgO to Mg(OH)2 of higher than 60% is obtained using calcination temperatures of 1000°C and below. At these temperatures medium reactive MgO was formed. The extend to which dead burnt MgO (obtained after calcination at 1200°C and higher) may be rehydrated is dependent on the calcination time, but even after 1 h and using magnesium acetate as a hydrating agent only 40% of the initial product has rehydrated to Mg(OH)2. After 4 and more hours of calcinations at 1200°C, a maximum of approximately 14% of the initial MgO is rehydrated back to Mg(OH)2. Thermogravimetric analysis was performed on the various compounds to determine the amounts of Mg(OH)2 that formed. 相似文献
79.
介绍用X-射线荧光光谱仪测定钛铁中Si、Mn、P、Al含量的方法,通过试验确定了合适的研磨时间、压力和保压时间,用压片法制样,建立了各元素的工作曲线,各元素的测定范围分别为Si3.00%~6.00%,Mn1.00%~3.00%,P0.030%~0.070%,Al5.00%~9.00%。通过强度测量得到测定Si、Mn、P、Al的相对标准偏差分别为0.074%、0.308%、0.383%、0.040%,精密度满足测试要求。将该方法测定结果与化学法比对,准确度满足国家标准方法分析误差的要求。 相似文献
80.