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应用紫外吸收光谱和荧光光谱研究了新型含硒席夫碱2-苄基亚胺基次甲基-4-(3-苄基亚胺基次甲基-4-羟基-苯硒基)苯酚(BBHP)与人血清白蛋白(HSA)之间的相互作用.结果表明,在生理pH值条件下BBHP主要通过形成复合物的静态猝灭方式使HSA的内源荧光得以强烈猝灭;BBHP与HSA主要有1个结合位点数,298 K时的结合常数为1.392×106 L·mo1-1;该结合反应为自发的放热过程,相互作用力主要为氢键和范德华力.根据F(o)rster无辐射能量转移理论计算了两者之间的结合距离r=2.42 nm,同时考察了BBHP对HSA构象的影响. 相似文献
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聚合物的络合性能是决定其是否可用作阻垢剂的关键。为考察新型改性产品天冬氨酸-苹果酸共聚物(PAMA)的络合性能,以其与Ca~(2+)络合量为评价指标,参照静态阻垢法,研究了不同水质和工况条件下PAMA在碳酸钙过饱和溶液中的络合性能。结果表明,单一Ca~(2+)条件下,PAMA投加量为4 mg?L-1时,络合效果最佳,络合量最大,为1632.78mg?g-1;Fe~(3+)、Cu~(2+)及其混合离子的加入均削弱PAMA的络合性能,而Zn~(2+)则提升其性能;Ca~(2+)/Zn~(2+)、Ca~(2+)/Cu~(2+)、Ca~(2+)/Fe~(3+)、Ca~(2+)/Fe~(3+)/Zn~(2+)/Cu~(2+)条件下,PAMA投加量为20 mg?L-1时,其络合效果最佳,络合量最大,分别为1681.00、1460.04、1465.09、和1464.11 mg?g-1。由此可见,PAMA具有良好的络合性能,是碳酸钙的优秀阻垢剂。 相似文献
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黄立伟江向平陈超黄枭坤聂鑫许经东王和鹏蒋泽云 《硅酸盐学报》2021,(4):648-658
采用传统固相法制备Ca1-xLaxBi_(2)Nb_(2)O_(9)(CBN-xLa,x=0.00,0.02,0.04,0.06,0.08,0.10)陶瓷,研究了La^(3+)掺杂对CaBi_(2)Nb_(2)O_(9)陶瓷的晶体结构、微观形貌、介电性能、压电及铁电性能以及高温导电机制的影响.结果表明,适量的La^(3+)取代Ca^(2+)优化了晶体结构,细化晶粒,通过施主掺杂降低了氧空位,有效地改善了CaBi_(2)Nb_(2)O_(9)陶瓷的电性能.其中Ca0.92La0.08Bi_(2)Nb_(2)O_(9)是最优组分,获得压电性能d33、Curie温度T_(C)和剩余极化强度2Pr分别为11.7 pC/N、905℃和9.51μC/cm^(2),并且在550℃条件下的tanδ为3.87%,退火处理后,所有组分样品在800℃条件下均保持较稳定压电性能.复阻抗谱表明阻抗是由晶粒晶界共同作用,导电机制与氧空位有密切关系,且La^(3+)能有效提高高温电阻率,使得其在高温传感器中具有应用潜力. 相似文献
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本文采用醚胺类捕收剂D-609作为磷矿反浮选脱硅捕收剂,通过纯矿物试验和矿物表面Zeta电位分析,探索了Ca~(2+)、Mg~(2+)、Fe~(3+)、Al ~(3+)对石英和磷灰石浮选的影响。试验结果表明:Al ~(3+)、Fe~(3+)可以明显抑制石英的上浮;Ca~(2+)在酸性条件下对石英有较弱的抑制作用,在碱性条件下可以活化石英;Mg~(2+)在酸性和碱性条件下可以抑制石英的浮选;Ca~(2+)、Mg~(2+)、Fe~(3+)、Al ~(3+)对磷灰石浮选的影响较小。 相似文献
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用D_2EHPA、TOA、兰113A和煤油乳状液膜体系,研究了Hg~(2+)的迁移富集行为。在适宜条件下,Hg~(2+)的迁移率达99.7%以上。在此条件下,许多共存离子如Cu~(2+)、Pb~(2+)、Zn~(2+)、Sn~(4+)、Co~(2+)、Ni~(2+)、Cd~(2+)、∑RE~(3+)、Ca~(2+)、Mg~(2+)、Al~(3+)、Fe~(3+)和Mn~(2+)等都不被迁移,只有Hg~(2+)能与这些离子得到很好的分离。已成功地应用于测定水和工业废水中的痕量汞,结果相当满意。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献