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991.
992.
RELATIONSHIP BETWEEN THE CHANGES OF THE FAST PHASE OF MILLISECOND DELAYED LIGHT EMISSION AND THE PROTON RELEASED BY THE OXIDATION OF WATER 总被引:1,自引:0,他引:1
The phosphorylation uncouplers suppressing the proton gradient across the thylakoidmembrane can also affect the fast phase of millisecond delayed light emission (ms-DLE) atflash light intensity strong enough to saturate the Hill reaction. At the concentration ofsame uncoupling degree, nigericin decreases the fast phase DLE much more than NH_4Cl.Omitting the terminal acceptor in the reaction mixture or adding DBMIB to inhibit PQ oxi-dation diminishes the slow phase DLE and affects the fast phase slightly, while DCMU orHOQNO which inhibits electron transport between PSII and PQ, diminishes both phases ofms-DLE. These results indicate that the proton gradient responsible for the enhancement ofthe fast phase DLE is more intimately linked to the thylakoid membrane, and is mainlyrelated to the proton release from water oxidation and not to the turnover of plastoquinone. 相似文献
993.
994.
用荧光光谱法研究了毒蛋白Cry I Ab在溶液中的构象。结果表明,pH值增大时,毒蛋白的荧光强度也增大,至pH=11时荧光强度已达最大值;甲醇、乙醇及异丙醇等有机溶剂引起毒蛋白荧光发射波长蓝移和荧光强度增大,至有机溶剂的浓度超过某一阈值后荧光发射波长不再蓝移;丙酮能完全猝灭毒蛋白Cry I Ab的荧光,丙烯酰胺能猝灭Cry I Ab86%的荧光,而KI对毒蛋白的荧光无猝灭作用,由此推断Cry I Ab的大部分色氨酸残基位于分子表面富含负电荷的区域中。 相似文献
995.
[Fe(MoS_4O)_2] [N(C_2H_3)_4]_3 cluster compound with di-end-oxygen ligands has been prepared and characterized by the X-ray diffraction method. The compound crystallizes in a monoclinic space group P2_1/n with lattice parameters a=13.019(4), b=16.959(5), c=18.234(5), β=97.34(2)(°), Z=4. The final agreement factors are R=0.0740, Rw=0.0598. The terminal bond length, Mo-S_t and bridged one, MO-S_b for the compound are much longer than the counterpart without end-oxygen ligand. It possibly suggests that low valence of molybdenum and smaller electronegativity of sulphur than oxygen lead to the charge transfer as S→Mo→O. 相似文献
996.
997.
〕本文首次将多目标优化与逐步回归设计相结合对反相色谱三元流动相的最佳组分进行了选择,并以去痛片组分与内标物的分离为例对方法和编制的程序进行考核。实验证明本方法简易、可靠。 相似文献
998.
999.
An efficient procedure for the synthesis of caffeoyl-and galloyl-containing β-diketoacid derivatives linked byarylamide was reported by,in the key step,dissolving the corresponding phenyl methyl ketone in THF/DME in thepresence of NaOMe as base and dimethyl oxalate as oxalylation reagent,and then separating the sodium ketoe-nolate ester.The resulting β-diketoacids underwent further condensation reaction with o-phenylenediamine to gen-erate quinoxalone derivatives in good yield,rather than 2-benzimidazol.The preliminary ion binding properties ofquinoxalone derivatives were also investigated.UV-Vis spectra showed that these compounds could selectively rec-ognize Cu~(2 )ion in ethanol and form a 1∶2 complex. 相似文献
1000.
A study of the effect of drug, kanamycin, on the growth metabolism of recombinant Escherichia coli B 1 was carded out by microcalorimeter monitoring of the metabolic activity of treated cells. Power-time curves of growing recombinant Escherichia coli cell suspensions, treated with different kanamycin doses, were recorded. The extent of the effect was evaluated by changes in the slopes of the microcalorimetric curves and the kinetics of the drug action was interpreted from the time at which these changes reached their maximum values and maintained their maximum values. Experimental dose-effect relationships conform to the median-effect principle of the mass-action law: fa/(1-fa)=(D/D50)^m. A plot of y=lg[(fa)^1-1]^-1 versus x=lg D gives the slope m, D50 and R∞. The experimental results revealed that high concentration of kanamycin had an inhibitory effect on the growth of recombinant Escherichia coli B 1 in the lg phase, and had a promoting effect in the stationary period. Moreover, it was demonstrated that microcalorimetry was a reliable method for the detection of modulatory effects in biology. 相似文献