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61.
细胞动力学研究VIII.Na2SeO3对黑根菌作用特征 总被引:1,自引:0,他引:1
The Characteristics of the action of Na2SeO3 on Rhizopus nigrocans has been studied by means of microcalorimetry, the relationship between growth rate constants and the concentration of Na2SeO3 is
k=0.03608exp[-0.003608(c+8.60)2]
It was found that Na2SeO3 of low concentration has promoting action on the growth of Rhizopus nigrocans cells, and high concentration of Na2SeO3 has inhibitory action. The study has provided a lot of information on the bioaffect of selenium and the research of toxicology. 相似文献
k=0.03608exp[-0.003608(c+8.60)2]
It was found that Na2SeO3 of low concentration has promoting action on the growth of Rhizopus nigrocans cells, and high concentration of Na2SeO3 has inhibitory action. The study has provided a lot of information on the bioaffect of selenium and the research of toxicology. 相似文献
62.
Annals of Global Analysis and Geometry - In this paper, we study a problem of finding compact hypersurfaces of prescribed mean curvature with free boundary in a ball. We transform the problem to an... 相似文献
63.
64.
钼钨铌磷杂多化合物的研究(Ⅰ):杂多酸的合成和表征 总被引:4,自引:0,他引:4
提出了分步酸化一分步加料合成[PNb_2Mo_xW_(10-x)O_(40)]~(5-)(x=0,2,4,6)系列杂多酸的方法,给出了最佳配料比和生成反应的pH值,并进行了红外、紫外、极谱、电位滴定及热稳定性研究。 相似文献
65.
66.
以Mg(OH)2共沉淀和阳离子交换树脂作为离线预富集方法,建立了天然水体中溶解态硅电感耦合等离子体质谱(ICP-MS)测定方法。实验采用NaOH作为Mg(OH)2沉淀引发剂,以共沉淀方式将溶解态硅元素从天然水体中分离富集,再利用阳离子交换树脂将基体Mg2 清除,并对洗脱液流速、共沉淀碱度等条件进行优化选择。结果显示:Mg(OH)2共沉淀步骤可定量回收溶解态硅,控制溶液通过阳离子交换树脂的速率可将硅元素与基体Mg2 完全分离而不会造成损失。不同基体的水样的加标回收率为99%~105%,方法检出限为4.5μg/L(3S,n=8),方法精密度RSD小于3%。 相似文献
67.
In this work, the surface properties of novel sugar-containing polymers, α-allyl glucoside (AG)/acrylonitrile (AN)copolymers, were studied by contact angle, protein adsorption and cell adhesion measurements. It was found that the contactangle of the copolymer films decreased from 68° to 30° with the increase of AG content in the copolymer. The adsorptionamount of bovine serum albumin (BSA) and the adhesive macrophage onto the film surface also decreased significantly withincreasing α-allyl glucoside content from 0 to 42 wt% in the copolymer. These preliminary results reveal that both thehydrophilicity and the biocompatibility of polyacrylonitrile-based membranes could be improved by copolymerizing acrylonitrile with vinyl carbohydrates. 相似文献
68.
69.
The reaction of Cu(CH(3)CN)(4)ClO(4) with 2-pyridylacrylic acid (2-HPYA) affords an unusual mixed-valence Cu(I)-Cu(II) 3-D framework ([Cu(II)(2-PYA)(2)](3).[Cu(I)(2-PYA)](2).(H2O)(2))n (1) with a novel topology which features Cu(II) dimeric units (or paddle-wheel unit). The almost perpendicular coordinating direction between the N atom of pyridyl and the O atom of carboxylate groups may be responsible for the formation of such a novel network. 相似文献
70.
Xi Li Yi Liu Jun Wu Huigang Liang Songsheng Qu 《Journal of Thermal Analysis and Calorimetry》2002,67(3):589-595
The action of three kinds of the selenomorpholine compounds on a strain ofEscherichia coli was studied by microcalorimetry. Differences in their capacities to affect the metabolism of this bacterium were observed.
The extent and duration of the effect on the metabolism as judged from the rate constant (k) of Escherichia coli (in log phase) varied with the different drugs. The kinetics show that selenomorpholine compounds had an effect on the metabolism
process of Escherichia coli. The k of Escherichia coli in the presence of the drugs increased with the increasing concentrations of the drugs (C) at low concentration; but at high concentration, the rate constant decreased with the increasing concentrations of the drugs.
The experimental results reveal that the sequence of antibiotic activity of selenomorpholines is: N-selenomorpholinemethyl
succinimide and its hydrochloride>N-(α-selenomorpholinebenzyl) succinimide.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献