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碱土金属与萘啶酸配合物荧光特性的研究及其应用 总被引:2,自引:0,他引:2
研究了碱土金属(Mg,Ca,Sr和Ba)离子与喹诺酮类药物萘酸配合物的荧光特性,发现在pH7~9介质中,碱土金属离子与萘啶酸可形成稳定的荧光配合物,其荧光强度随碱土金属离子半径的减小而呈现有规律的增强效应,其中镁离子与萘啶酸配合物的荧光萘啶酸强58倍,利用此配合反应发展了镁离子增强一份导数荧光激发光谱测定萘啶酸的分析方法,其检出限为0.015μg/mL。可直接测定尿液中萘啶酸含量,其回收率为96. 相似文献
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一次验证镁与NaHCO3溶液反应得到H2的实验中,发现镁能与饱和Na2CO3溶液作用持续释出H2,为此通过分析Mg/H2O体系的热力学数据和研究其动力学机理认为实现镁与水溶液作用能持续释出H2的有效方法:在溶液中加入能破坏氢氧化镁保护层的某些离子。并设计有关实验证明:在碱性溶液中,若加入能与Mg2+形成稳定配合物的其他阴离子(如甘氨酸根离子、草酸根离子、EDTA等),则镁就能与碱性的盐溶液持续反应。 相似文献
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本文用波谱及高压液相色谱(HPLC)方法研究了二氯代三-2-吡啶甲基胺的铁(Ⅲ)配合物(FeTPACl_2ClO_4),三─6─甲基─2─吡啶甲基胺合铁(Ⅱ)与苯甲酸的配合物(Fe(Ⅱ)TLAOBzClO_4)同单过氧化邻苯二甲酸六水合镁盐(monoperoxyphthalicacid,magnesiumsalthexahydrate,即MPPA)的反应。提出了过氧键的两种断裂(即均裂和异裂)机理,分析了中心离子价态、配体结构等因素对反应机理的影响;并通过FeTPACl_2ClO_4与间氯代过氧代苯甲酸(mcPBA)的反应,研究了过氧酸结构对反应机理的影响。实验结果表明:就过氧酸中过氧键发生均裂的程度而言:三价铁配合物与过氧酸的反应>二价铁配合物与过氧酸的反应;MPPA反应体系>MCPBA反应体系。 相似文献
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研究了在不同PH、浓度、时间、温度、离子强度和螯合剂的条件下, 用不同浓度的硝酸预处理的氧化铝吸附剂自锌(II)-硫氰酸根配合水溶液中吸附Zn^2^+及SCN^-的特性, 并与自简单锌盐、硫氰酸盐水溶液中的吸附特性相比较, 结果表明配合物体系中的吸附作用不同于非配合物体系, 除了主要以离子交换机理进行外, 还可能在氧化物/水界面上发生配位吸附作用。 相似文献
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本文报道用PH滴定法测得KNO3水溶液中邻苯二酚-3,6-二甲撑亚氨基二乙酸(CBMIDA, H6L)的六级酸解离常数及CBMIDA的镁(II)、钙(II)、锶(II)、钡(II)、镍(II)、锌(II)、钴(II)、镉(II)、锰(II)、铜(II)、铁(II)、钍(IV)和铀酰离子的配合物稳定常数及配合物的质子化常数. 讨论了CBMIDA的逐级酸离解的动态平衡机理以及金属离子与CBMIDA形成的各种配合物的配位形式. 相似文献
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π-烯丙基卤化铁含氮配位体的络合结构被认为是铁体系催化丁二烯聚合反应的活性中心,所以合成具有这种结构的模型化合物并研究其催化活性是很有意义的。我们曾合成了π-烯丙基氯化铁三吡啶配合物并研究了它对丁二烯聚合的催化活性,但所得配合物混有近等当量的卤化镁难以分离。Nesmeyanov曾合成π-烯丙基卤化铁三羰基化合物η~3-C_3H_5FeX(CO)_3(X=Cl,I)。我们的实验结果表明这类配合物对丁二烯聚合无催化活 相似文献
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不同水煤浆分散剂与煤之间的相互作用规律研究 Ⅴ. 煤在分散剂水溶液中的溶出离子及其对CWS性质的影响 总被引:2,自引:6,他引:2
通过原子吸收和等离子体原子发射光谱法,研究了6种不同分散剂对14种煤溶出Ca2+、Mg2+、Fe3+(Fe2+)、Al3+、SiO32-离子的影响。结果表明,煤中溶出高价离子的数量,主要取决于分散剂与高价离子间的相互作用特征,以及矿物质的种类和数量。煤在不同分散剂水溶液中溶出高价离子的多少,并不单纯与水煤浆(CWS)的流变性或煤的成浆性具有相关性。煤中矿物质对CWS性质的影响,是多种因素综合作用的结果,溶出离子的种类和数量只是其中的重要因素之一。 相似文献
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提出了一种由层状前体合成单一晶相镁铁尖晶石的新方法,首先对Mg-Fe(Ⅱ)- Fe(Ⅲ)水滑石的制备进行了系统研究,成功合成了Mg^2+/Fe^2+/Fe^3+摩尔比分别 为1/2/1,4/5/3,2/1/1的系列水滑石层状前体,结果表明在以上三种投料 比下均可制备出晶型较好的水滑石层状前体,并探讨了合成条件对晶体结构的影响 规律。在此基础上,利用X射线衍射、振动样品磁强计和穆斯堡尔谱等手段研究了 层状前体焙烧产物的结构、组成、磁性及微观信息,研究表明当 Mg^2+/Fe^2+/Fe^3+投料摩尔比为2/1/1时,焙烧层状前体可得到晶相单一的尖晶 石型铁氧体。 相似文献
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铬在纳米晶氧化铁中的掺杂研究 总被引:1,自引:0,他引:1
Fe^3^+(Cr^3^+)/Fe^2^+混合离子(M^3^+/M^2^+原子比为2:1)共沉淀法制备的Cr~2O~3掺杂量O~14%(质量分数)系列纳米氧化铁,XRDRietveld分析表明全是晶态γ-Fe~2O~3和非晶Fe~2O~3的混合物。非晶丰度范围为21.72%~48.6%。Mossbauer谱分析发现,掺杂量少于2%(质量分数)的氧化铁,晶态和非晶态均是磁性六线谱,大于2%(质量分数)后,另出现强度随掺杂量增加线性递增的超顺磁二线谱。共沉淀过程中,Fe^3^+为主夹杂定量Cr^3^+的Fe^3^+水合配合物网络与Cr^3^+为主夹杂定量Fe^3^+的Cr^3^+水合配合物网络,是形成磁性氧化铁和非晶非磁氧化铁的基础,后者镶嵌在前者中间,阻碍其晶化和晶粒长大,自身形成非晶非磁含铬氧化铁。 相似文献
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Gabapentin undergoes intramolecular cyclization by alkylamine nucleophilic attacking on carboxylate carbonyl. And the above self-dehydration condensation can produce gabapentin lactam which has some toxic effects. Therefore, in order to decrease the above subsidiary reaction, the effects of several metal ions on the reaction mechanism and the potential barriers of self-dehydration condensation of gabapentin are analyzed. Each molecular structure of gabapentin in the presence of several metal ions is optimized using the density functional theory(DFT) with B3LYP method at the 6-311+G(d,p) basis set level. And its geometric and thermodynamic parameters are also investigated. The calculated results showed that gabapentin can form stable complexes with divalent metal ions and exhibit the highest affinity for small and highly charged metal cations. The binding ability of these metal ions with gabapentin ranks in an order of Fe~(2+) Zn~(2+) Mg~(2+) Ca~(2+) Na~+ K~+. Besides, the potential barriers of subsidiary reaction of gabapentin increase obviously in the presence of several metal ions than that of free gabapentin. This means that the above metal ions can inhibit effectively the intramolecular cyclization of gabapentin. 相似文献
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A hydroxyl substituted phenolic Schiff base 1, used as sensor for detection of Zn^2+, was synthesized and investigated. It was found that a strong fluorescence emission was observed when 1 bound to Zn^2+ in acetonitrile, whereas no fluorescence emission was detected when 1 bound to other metal ions (Fe^2+, Co^2+, Ni^2+, Cu^2+, Cd^2+, Hg^2+, Mg^2+, Pb^2+, Ca^2+, Ba^2+, Sr^2+) except for Mg^2+, for which a weak fluorescence emission was detected in the same condition. Competition experiment showed that no obvious interference was observed in its fluorescence while 1 performed the titration with Zn^2+ in the different mixtures of metal ions. To understand the site where Zn^2+ coordinated to the ligand and the mechanism of binding, three other hydroxyl substituted phenolic Schiff bases 2-4 were synthesized and their binding reactions with Zn^2+were also investigated. 相似文献
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竹红菌乙素(HB)能与Mg2+和Zn2+形成重复单元数为5-20的配位聚合物(Mg2+-HB,Zn2+-HB),利用紫外-可见(UV-Vis)吸收光谱,傅里叶变换红外(FTIR)光谱,核磁共振氢谱(1H NMR)对其进行了表征.Mg2+-HB和Zn2+-HB的单重态氧量子产率分别为HB的1.2倍和0.42倍.瞬态吸收实验表明:氧气能够猝灭Mg2+-HB和Zn2+-HB的三重态,其效率可超过96%.系间窜越效率(φT)和将能量传递给氧气并能产生单重态氧的三重态光敏剂的比例(fT△)对HB及其金属配合物的单重态氧量子产率有较大影响.电子自旋共振(EPR)实验结果表明:Mg2+-HB和Zn2+-HB产生半醌负离子自由基的能力较弱,进而降低了Mg2+-HB和Zn2+-HB光敏产生超氧负离子自由基的能力.紫外-可见吸收光谱与小牛胸腺脱氧核糖核酸(CT DNA)熔链温度实验表明:Mg2+-HB和Zn2+-HB可通过静电作用与DNA结合.有氧条件下,Mg2+-HB,HB和Zn2+-HB对小牛胸腺DNA的光敏损伤效率分别为32%,25%和22%.活性氧猝灭实验表明Mg2+-HB主要通过单重态氧光敏损伤DNA. 相似文献
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《结构化学》2021,(4):465-472
A new ligand [1-{2-(2-pyridyl)-benzo[d]imidazole}-2-(5-hydroxyisophthalic acid) ethane] was used to synthesize cadmium and cobalt based florescent organic frameworks successfully under solvothermal conditions. Single-crystal X-ray crystallography of both complexes as well as their thermal stability and luminescence properties was investigated. Much emphasis was placed on the newly synthesized Cd-complex which shows great sensitivity for the detection of Fe~(3+) ions and could be used as a potential probe to detect the Fe~(3+) ions. 相似文献
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The zeta-potential of montmorillonite-water colloid systems of different districts and distinct types are different. In this study the zeta-potentials were determined for montmorillonitewater colloid system of different districts and types. The relationship of octahedral(Fe~(3+)+Mg~(2+)) and the cell parameter b0 dimension of montmorillonites with the zeta-potential of montmo rillonite-water colloid systems were discussed. 相似文献
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The UV/VIS spectra for pyridine solution of complexes [Fe_2MO(CH_3COO)_6Py_2]·Py and THF solution of complexes Fe_2MO(CCl_3COO)_6(THF)_3 were studied. The d-d transitions were assigned and the ligand field parameters(B,D_q,β) were calculated for the related metal ions according to ligand field theory (Tanabe-Sugano diagram) in terms of O_h symmetry and reasonably good fits were obtained for the calculated and observed frequencies. The calculated results show that (1) the larger the ionic potential for M~(2+) ion, the larger the values of B, D_q for Fe~(3+) ion (2) the ligand field parameters of metal ions vary in parallel with the electronagativity of R in RCOO~-. 相似文献