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LaCl3提高菠菜光系统Ⅱ活性的作用机制 总被引:2,自引:0,他引:2
The effect of LaCl3 on the K3Fe(CN)6 (FeCy) reduction rate and the oxygen-evolving rate of PSU particles of spinach, and the spectral characterization of the D1/D2/Cytb559 of a PSII reaction center complex consisting of three polypeptides from spinach were studied. The experimental results showed that LaCl3 could significantly accelerate the transformation from light energy to electric energy, the electron transport, water photolysis and oxygen evolution of PSII of spinach, which was related to the spectral characterization of the D1/D2/Cytb559 complex.Soret band and Q band of Chl-a of UV-vis spectrum of D1/D2/Cytb559 complex were blue shifted, and the fluorescence emission peak was blue shifted in LaCl3 treated spinach compared with that in the control. The EXAFS (extended X-ray absorption fine structure spectroscopy) revealed that La^3 was coordinated with 8 nitrogen or oxygen atoms in the first coordination shell with La-N or La-O bond length of 0.254 nm, and with 6 nitrogen or oxygen atoms in the second coordination shell with La-N or La-O bond length of 0.321 nm in the D1/D2/Cytb559 complex. The CD suggested that the secondary structure of D1/D2/Cytb559 complex have been litfie affected by the treatment of LaCl3. 相似文献
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Pr原子特殊的电子层结构使其具有多方面的催化特性.实验发现质量分数为0.7%的PrCl3就可使漆酚(U)于110℃固化成膜的时间从5h降低到1h.用可见分光光度法、电子能谱、紫外和红外光谱等方法研究U在PrCl3作用下的固化成膜历程.结果表明,在Pr(Ⅲ)催化U聚合的过程中首先是U与PrCl3发生配位作用,生成U镨配合物(UPr),然后该配合物分子中的Pr(Ⅲ)催化U聚合成体形结构的高分子化合物. 相似文献
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LaCl3对欧洲李(Prunus domestica) GF43试管苗根系生长及衰老作用的影响 总被引:1,自引:1,他引:1
研究了2.5 μmol·L-1 LaCl3在GF43试管苗根系生长及衰老过程中的作用. 结果表明, LaCl3可促进GF43试管苗根系生长及干物质积累, 显著提高超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)和过氧化物酶(POD)等抗氧化酶活性, 降低超氧阴离子自由基(·O-2)产生速率、丙二醛(MDA)含量和膜透性, 对细胞膜结构具有稳定作用, 从而延缓试管苗根系的衰老进程. 此研究对解决核果类果树工厂化育苗过程中的生根及移栽问题具有一定的参考价值. 相似文献
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利用DTA研究了LaCl3-KCl-LiCl三元系统相图。发现该相图由二个赝三元相图构成。相图中有五个液相面, 七条二次结晶线, 三个三元无变点, 它们分别为低共熔点E1[W(LaCl3)=0.115, W(KCl)=0.474, W(LiCl)=0.411, 345℃],E2[W(LaCl3)=0.494, W(KCl)=0.216, W(LiCl)=0.290, 410℃]和三元转熔点P[W(LaCl3)=0.600, W(KCl)=0.108, W(LiCl)=0.292, 429℃]。 相似文献
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高浓度LaCl3抑制黄瓜(Cucumis sativus Linn)光系统Ⅱ(PS Ⅱ)活性 总被引:3,自引:0,他引:3
研究了高浓度LaCl3对黄瓜(Cucumis sativus Linn)光系统Ⅱ(PSⅡ)光诱导荧光动力学参数、低温荧光光谱和放氧活性的影响。结果表明,随着黄瓜体内LaCl3浓度的升高、其荧光量子产率、PSⅡ最大光化学效率、放氧活性和电子传递速率都明显降低。低温荧光分析表明,低浓度LaCl3引起激发能更多的分配给PSⅡ。高浓度LaCl3对黄瓜幼茁的抑制作用表现在对类囊体膜结构的破坏。进而导致PSⅡ光合活性下降,并最终抑制黄瓜生长。 相似文献
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CuCl对Et3NHCl/AlCl3离子液体催化性能的影响 总被引:12,自引:0,他引:12
用CuCl对Et3NHCl/AlCl3离子液体进行改性,并考察了其对异丁烷-丁烯烷基化反应的催化性能. 结果表明,烷基化油的收率达到178%,C8组分的含量达到85%,辛烷值(RON)达到94.8. 通过结构组成及电荷分布分析可知,在CuCl改性的Et3NHCl/AlCl3离子液体中形成了新的配位结构AlCl4CuCl-,它作为更好的碳正离子受体,在反应过程中可降低碳正离子的浓度,进而降低烯烃的聚合程度,抑制较长碳链烷烃的生成,改善烷基化油的组成. 相似文献
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Synthesis and Crystal Structure of the Lewis Acid‐Base Adduct AlCl3·C3N3Cl3 The reaction between cyanuric chloride (C3N3Cl3) and the strong Lewis acid AlCl3 yielded colorless crystals of the adduct AlCl3·C3N3Cl3. The crystal structure was determined by single crystal X‐ray diffraction at room temperature and was solved in the space group with Z = 4, a = 7.3802(7) Å, b = 9.688(1) Å, c = 16.272(2) Å, α = 72.80(1)°, β = 89.97(1)°, γ = 87.23(1)°, and V = 1110.0(2) Å3. In the crystal structure, AlCl3 is closely associated to the triazine ring with Al–N distances of 2.042(3) Å and 2.067(4) Å, respectively. The AlCl3·C3N3Cl3 units are connected with each other via intermolecular N···Cl donor–acceptor interactions, forming tape‐like arrangements in the ac‐plane, with tapes running parallel to the a‐axis. 相似文献
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The Layer Structure of Cyameluric Chloride C6N7Cl3 A solid state reaction of cyanuric chloride (trichloro‐s‐triazine C3N3Cl3) with sodium dicyanamide (NaN(CN)2) yielded some yellow, plate‐like crystals of cyameluric chloride (trichloro‐s‐heptazine C6N7Cl3). The crystal structure was determined by single crystal X‐ray diffraction at 220 K and was solved in the monoclinic space group C 2/c (no. 15) with Z = 24, a = 2319.4(4) pm, b = 1348.8(1) pm, c = 2063.4(3) pm, β = 118.38(2)° and V = 5.680(1) nm3. In the structure, the molecules of C6N7Cl3 are forming layers parallel to the ab‐plane, which are separated from each other by a gap of approximately 300 pm. In each of these layers, the molecules seem to be arranged around pseudo‐threefold axes, showing an almost trigonal structure pattern. 相似文献
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NdCl3-FeCl3-石墨层间化合物的合成 总被引:1,自引:0,他引:1
采用熔盐交换法成功地合成了NdCl3FeCl3GIC, 用XRD 技术和X射线能谱仪(EDS) 对其层间结构及各元素的相对含量进行了表征。研究表明, 其结构为2,3 ,4 阶混合结构,3 阶NdCl3 的特征层间距为1-6536 ±0-0024 nm , 并探讨了稀土氯化物石墨层间化合物的形成机制。 相似文献
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采用一价铜盐为催化剂、二甲基甲酰胺为溶剂,在均相体系中催化3-氯-1-丁烯异构化生成1-氯-2-丁烯.考察了溶剂、反应温度、催化剂种类和加入量对反应的影响,研究发现反应温度和催化剂的加入量对异构化反应有较大影响.在最优条件3-氯-1-丁烯1 mL,二甲基甲酰胺9 mL,CuCl 0.10 g,60℃反应5 h,产物和原料的浓度比为3.88 mmol L-1.采用在线红外光谱对反应过程进行监测,检测到有红外吸收峰在反应过程中先增加后减少的变化过程,提出了可能的反应机理. 相似文献
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Ni2+的引入对离子液体烷基化催化性能的影响 总被引:2,自引:0,他引:2
Thealkylationofisobutanewithbuteneisanim portantprocessforthe productionofhigh qualitypetroleum .In placeofconcentratedsulfuricacid ,Et3NHCl/AlCl3ionicliquidhasbeenusedinthereac tionwithfairlygoodeffect[1] ,butthereisstillabigdifferencecomparedwiththeresultsofconcentratedsulfuricacid .TheC8contentinthealkylatesobtainedwithconcentratedsulfuricacidwas 72 1% [2 ] ,butitwasonly 5 6 %withtheionicliquid .ThekeyreactioninthealkylationishydrogentransferfromC+8toC08[3] ,andthisisthemainreasonforth… 相似文献
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H. Sabrowsky E. Feldbaum-Mller K. Fischer S. Sitta P. Vogt V. Winter 《无机化学与普通化学杂志》1996,622(1):153-156
The Crystal Structures of α- and β-K3OCl The orange coloured compound K3OCl has been prepared. It exists in a low temperature modification (α-K3OCl) and a high temperature modification (β-K3OCl). The transition temperature is 364 ± 5 K. The crystal structures were determined by x-ray diffraction. α-K3OCl crystallizes at room temperature in the orthorhombic space group Pbnm (Z = 4) with the cell parameters a = b = 723.9(2) pm and c = 1 027.7(2) pm in the anti-GdFeO3-structure type. The high temperature modification β-K3OCl crystallizes (Z = 1) in the cubic space group Pm3m in the β-Ag3SI-structure type with a = 516.2(2) pm (T = 393 K). 相似文献
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NH4CaCl3, the Reactive Intermediate Phase in a Synthesis of CaCl2 The reaction of CaCO3 with NH4Cl leads to formation of CaCl2. In this reaction an intermediate phase is formed, that is be characterized as NH4CaCl3. This intermediate phase crystallizes in the GdFeO3 type and decomposes at elevated temperatures to yield CaCl2 and NH4Cl. The formation and the decomposition of this intermediate phase as well as the formation of CaCl2 were studied with X-ray and thermoanalytical methods. 相似文献
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稀土羧酸盐,如辛酸盐,硬酯酸盐和环烷酸盐等组成的催化体系对共轭双烯烃聚合具有良好的活性和定向效应。但体系中要有第三组分的存在,通常采用的是烷基氯化铝,其作用是与羧酸盐羧基进行交换反应,是形成活性中心的必要条件。氯化稀土组成的体系由于自身组成含有氯离子而排除了第三组分的使用,从而简化了聚合工艺流程,有利于研究体系组分之间的反应。但是并非所有氯化稀土都适宜于这种研究,原因在于大多数氯化稀土络合物不溶于惰性有机溶剂。如氯化稀土醇合物对共轭双烯烃聚合有着相当高的活性,但是研究氯化稀土醇合物与烷基铝的反应却有着一定的困难。 相似文献