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许多乙酰芳胺类化合物具有优异的生物活性,例如除草剂苯噻草胺,可抑制细胞生长和分裂,防除稻田中禾本科杂草[1];杀菌剂甲霜灵可防治作物霜霉病[2]。本文将具有多种生物活性的嘧啶基团引入到乙酰芳胺结构中[3],合成下列10个未见文献报道的标题化合物Ⅰ,通... 相似文献
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Fashui?HongEmail author Xuefeng?Wang Chao?Liu Guoxing?Su Weiping?Song Kang?Wu Ye?Tao Guiwen?Zhao 《中国科学B辑(英文版)》2003,46(1):42-50
It was studied by spectroscopy that PSII reaction center complex consisting of three polypeptides, D1, D2 and Cytb559, were purified from PSII particle of CeCl3 treated spinach. The results of the experiment show that Ce3+ could improve the growth of spinach, and accelerate electron transport of PSII particles. Of chl-a of UV-Vis spectrum of
D1/D2/Cytb559 complex, Soret band was blue-shifted by 3 nm and Q band by 2 nm, respectively, and the fluorescence emission
peak was blue-shifted by 5 nm in CeCl3-treated spinach compared with the one in control. By the extended X-ray absorption fine structure (EXAFS) spectroscopy methods,
it has been found that Ce3+ is coordinated with 8 nitrogen atoms in the first coordination shell with Ce-N bond length of 0.253 nm, and Ce3+ with 6 oxygen atoms in the second coordination shell with Ce-O bond length of 0.32 nm. However, the secondary structure of
D1/D2/Cytb559 complex by circular dichroism (CD) spectroscopy has no significant change after CeCl3 treated. It might be that Ce3+ binds to porphyrin rings of chlorophyll and oxygen of amino acid residue of polypeptide in D1/D2/Cytb559 complex, and then
accelerates the primary reaction of PSII, intensifies function of P680+ primary electron donor of D1/D2/Cytb559, but there is little change in conformation of PSII reaction center complex. 相似文献
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The complexes of Ni (His) 2·H2O, Ni (Gly) 2·2H2O, Pd (His)Cl2·H2O and Pd(Gly) 2·2H2O were synthesized. And the IR, electronic absorption and photoacoustic spectra of these complexes were measured in solid state. The nature of the metal-carboxylate coordinate bond were deduced from the variation in the carboxyl stretching frequencies. And the d-d transition absorptions of these complexes were interpreted quantitatively with the 3d scaling radial theory. Therefore, the structural characterizations were also discussed with their spectral behaviors. 相似文献
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Abstract The photoacoustic(PA) amplitude and phase spectra of several kinds of rare earth (RE) complexes are reported and summarized briefly. It is observed that both the amplitude and phase spectra well characterize the different energy levels of the RE complexes. The phase angle of the RE complexes is associated with the relaxation time τ and the optical absorption coefficient β concerning with the π-π? transition and the f-f transitions, respectively. After individual detailed discussion of the phase spectra, a reasonable theoretical consideration is given to interpret the results. 相似文献
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In our early researches, lanthanum and cerium could enter plant and bind to porphyrin of chlorophyll to form Ln3+-chllorophyll. La and Ce greatly increase photosystem II (PSII) activity and PSII electron transport rate, and the fluorescence emission peaks of PSII are blue-shifted [1—4]. Do REEs coordinate with PSII reaction center complex in vivo? Moreover, do REEs coordinate with D1(30 kD)/D2(32 kD)/Cytb559 (~9 kD) reaction center complex of site of producing pri-mary reaction-p… 相似文献
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浊音声母的特点是低频信号显著:使用信号经过高频加重滤波器之后和之前的能量比可以反映语音信号能量集中的频率范围。据此,本文提出了一个将浊音声母从可能含有它的孤立字音中分隔出来并且进行分类和辨认的算法。对来自不同省分的八个讲者的语音数据进行分类和辨认实验,区分浊音声母和零声母两类的正确分类率达到98%以上。使用线性判别技术辨认各个浊音声母,平均正确辨认率达到86%。 相似文献
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Xu K Tang B Huang H Yang G Chen Z Li P An L 《Chemical communications (Cambridge, England)》2005,(48):5974-5976
This paper reports the synthesis, fluorescence properties, and biological applications of naphthofluorescein disulfonate (NFDS-1), as a red fluorescence imaging probe to detect intracellular H2O2. 相似文献
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应用光镊拉曼光谱系统俘获单个红细胞并收集其拉曼光谱,选择I1638/I1547比值为区分红细胞氧合及去氧态指标,比较分析地中海贫血HbH-CS和健康个体单个红细胞的氧循环过程的氧合和去氧能力及去氧态群体红细胞.结果发现,在氧循环的去氧态中,地中海贫血HbH-CS的I1638/I1547显著高于正常对照;氧合态的I1638/I1547也略高于正常对照.群体统计中,若以小于正常对照I1638/I1547的平均值为去氧态基准,则正常对照46%的红细胞达到去氧态.而地中海贫血HbH-CS仅有15%,表明地中海贫血HbH-CS红细胞的氧合能力较强,但去氧能力显著低于正常对照,而且地中海贫血HbH-CS红细胞个体差异较大.该研究在单细胞水平上,揭示了地中海贫血HbH-CS红细胞氧合,去氧能力以及细胞个体差异性,以评价其携氧功能,为诊断治疗提供一定的理论依据. 相似文献
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