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971.
972.
ZHANG Wei-wei CHEN Yu-chun LUO Zhao-feng WANG Ju-ying MA De-yi 《高等学校化学研究》2007,23(4):404-407
In this study, surface plasmon resonance (SPR) for monitoring 17β-eatradiol (E2) was developed. The small molecule E2 was immobilized on a CM5 sensor chip for an indirect competitive immunoassay to detect E2. The SPR response bahed on the antigen-antibody reaction was measured by injecting the sample solution into the flow system. The limitation of detection was 0.445 μg/L. The developed SPE-SPR system was applied to analyze the seawater samples. Recovery of E2 was 91.6%-93. 1%. Relative standard deviations(RSD) for the E2 assay were between 10.9%-15.1% (n = 3). The range of determination of E2 samples from the sewage in the coastal marine environ-ment was between ND(lower than detection limit) and ca. 11.78 ng/L. 相似文献
973.
纳米PbSnO3的制备及其燃烧催化性能的研究 总被引:1,自引:0,他引:1
Nanocomposite PbSnO3was synthesized by coprecipitation method , and its phase evolution process was investigated. The particle size, crystal form, and phase of samples were determined with XRD, TEM and EDS. The catalytic actiyity of sample on the thermal decomposition of RDX was investigated by DSC. The results show that nanocomposite PbSnO3with the diameter of 9 nm can be obtained by calcining at 600 ℃ for 2 h, which crystal is cubic (pyrochlore type). The catalytic actiyity of nanocomposite PbSnO3on the thermal decomposition of RDX is much higher than that of normal PbSnO3. The nanocomposite PbSnO3can decrease the peak temperature of thermal decomposition of RDX from 240.1 ℃ to 236.5 ℃, and the decomposition enthalpy ΔH of RDX increases 722 J·g-1 (about 70%). 相似文献
974.
An alternative method for anomeric deacetylation of fully acetylated carbohydrates has been developed using imidazole in methanol. 相似文献
975.
976.
977.
主要介绍了深圳市妇幼保健院在国内率先推出的产后家庭保健服务项目,总结了为2 800对母婴上门提供保健服务的临床意义和社会效益. 相似文献
978.
The fluorescent calcium ion indicator dye Fluo-3 and DNA-binding dye Hoechst 33342 were employed to determine, in a quantitative microspectrofluorometric study, the intracellular calcium ion concentration ([Ca~(2+)]_i) and the DNA content of individual living NIH3T3 cells. The well-separated excitation and emission properties of these dyes allowed us to establish for each cell both the phase of the cell cycle using DNA content and [Ca~(2+)]_i. We found that the transition from G_1, through S, to the G_2 phase is accompanied by a two-fold increase in [Ca~(2+)]_i. The [Ca~(2+)]_i was inhomologous in each phase of the interphase (G_1, S and G_2) although [Ca~(2+)]_i in the S and G_2 phases was never lower than certain threshold values in the G_1 and S phases respectively. [Ca~(2+)]_i in G_0 cells was lower than that in G_2 cells. These changes in [Ca~(2+)]_i suggest that [Ca~(2+)]_i may be an import regulator of cell cycle progression. 相似文献
979.
高分散纳米二氧化钛混合晶体的合成、结构与光催化性能 总被引:11,自引:0,他引:11
Using TiCl4 and urea as the raw materials and nanometric carbon black as plate, nanometric mix-crystals of rutile and anatase TiO2 were prepared at 100 ℃ for 10~180 min by homogeneous precipitation method. The effects of pH on the ratio of nanometer TiO2 mix-crystals were also discussed. TEM measurement indicates that the TiO2 is spherical particles, and the average diameter of the particles is 20 nm. XRD and TG-DTA were also used to characterize the nanometer mix-crystal materials. The photocatalytic experiment show that the mix-crystal material has the best photocatalytic reactivity. After being irradiated under the sunlight for 40 min, the compound can completely degrade the acid-red 3R. 相似文献
980.