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1.
本文研究了室温时K~3Fe(CN)~6,K~4Fe(CN)~6在酸碱条件下发生的固相配位化学反应。结果表明:K~3Fe(CN)~6与NaBH~4固相混合物室温下不反应,但加入固体氢氧化钠后,K~3Fe(CN)~6与NaBH~4的固相氧化还原反应在室温下很容易进行。K~4Fe(CN)~6与K~2S~2O~8的固相氧化还原反应在室温下能顺利进行,但当固体KOH存在时,反应明显受到抑制。K~3Fe(CN)~6与K~2C~2O~4.H~2O室温下无反应,但与H~2C~2O~4.2H~2O在室温时即发生固相取代反应。  相似文献   

2.
本文研究了室温时K_3Fe(CN)_6,K_4Fe(CN)_6在酸碱条件下发生的固相配位化学反应.结果表明:K_3Fe(CN)_6与NaBH_4固相混合物室温下不反应,但加入固体氢氧化钠后,K_3Fe(CN)_6与NaBH_4的固相氧化还原反应在室温下很容易进行.K_4Fe(CN)_6与K_2S_2O_8的固相氧化还原反应在室温下能顺利进行,但当固体KOH存在时,反应明显受到抑制.K_3Fe(CN)_6与K_2C_2O_4·H_2O室温下无反应,但与H_2C_2O_4·2H_2O在室温时即发生固相取代反应.  相似文献   

3.
本文用气相色谱、红外光谱和Mossbauer谱等手段, 研究了硝普钠与锰(II)、钴(II)、镍(II)、铜(II)氯化物在氢气氛中的固相反应, 发现过渡金属盐的存在或多或少地影响了硝普钠的分解方式, 其中CuCl~2.2H~2O与硝普钠室温时就反应生成Cu[Fe(CN)~5NO].χH~2O; 在较高温度下, CoCl~2.6H~2O和NiCl~2.6H~2O与硝普钠的固相反应催化了硝普钠迅速分解; 而氯化锰与硝普钠的固相反应与纯配合物较为接近。探讨了第一步反应可能的机理, 并计算了反应动力学参数。  相似文献   

4.
本文用气相色谱、红外光谱和Mossbauer谱等手段, 研究了硝普钠与锰(II)、钴(II)、镍(II)、铜(II)氯化物在氢气氛中的固相反应, 发现过渡金属盐的存在或多或少地影响了硝普钠的分解方式, 其中CuCl~2.2H~2O与硝普钠室温时就反应生成Cu[Fe(CN)~5NO].χH~2O; 在较高温度下, CoCl~2.6H~2O和NiCl~2.6H~2O与硝普钠的固相反应催化了硝普钠迅速分解; 而氯化锰与硝普钠的固相反应与纯配合物较为接近。探讨了第一步反应可能的机理, 并计算了反应动力学参数。  相似文献   

5.
本文详细考查了壳质胺,多孔玻璃和粗孔硅胶作为流动注射免疫分析免疫反应器基质的可行性,在此基础上将HRP催化H~2O~2氧化K~4Fe(CN)~6生成K~3Fe(CN)~6的反应,与H~2O~2和K~3Fe(CN)~6对luminol的共氧化化学发光反应相偶合首次提出了一种新的流动注射免疫分析的最终检测手段,由于酶促反应与化学发光反应在检测系统的不同位置进行,因而这种方法克服了已报道的流动注射化学发光免疫分析不能协调酶催化和化学发光反应的最佳pH,底物与酶不能充分接触及载体对光的散射等缺点,具有灵敏度高、精密度好等优点,该方法测定HRP及其标记物检测限均可达fmol级,测定时间为1-2min,相对标准偏差为3.9%。  相似文献   

6.
本文详细考查了壳质胺,多孔玻璃和粗孔硅胶作为流动注射免疫分析免疫反应器基质的可行性,在此基础上将HRP催化H~2O~2氧化K~4Fe(CN)~6生成K~3Fe(CN)~6的反应,与H~2O~2和K~3Fe(CN)~6对luminol的共氧化化学发光反应相偶合首次提出了一种新的流动注射免疫分析的最终检测手段,由于酶促反应与化学发光反应在检测系统的不同位置进行,因而这种方法克服了已报道的流动注射化学发光免疫分析不能协调酶催化和化学发光反应的最佳pH,底物与酶不能充分接触及载体对光的散射等缺点,具有灵敏度高、精密度好等优点,该方法测定HRP及其标记物检测限均可达fmol级,测定时间为1-2min,相对标准偏差为3.9%。  相似文献   

7.
合成了新型Co(Ⅲ)配合物trans-[(en)~2(NO~2)Co(O~2CC~5H~5N)](ClO~4)~2, 并通过紫外可见光谱、红外光谱、元素分析和X射线单晶衍射分析进行了表征。同时分别以[Fe(CN)~6]^4^-和[Fe(CN)~5(H~2O)]^3^-作为还原剂, 考察了该配合物被还原的反应动力学行为。结果表明两反应体系分别按外配位界机理和内配位界机理进行电子传递。在25℃, Ⅰ=0.5mol·L^-^1,trans-[(en)~2(NO~2)Co(O~2CC~5H~5N)]^2^+/[Fe(CN)~6]^4^-反应体系的前驱配合物离子对形成常数Q~i~p=29mol^-^1·L, 电子转移速率常数k~e~t=2.4×10^-^4s^-^1,电子转移过程的活化焓△H^≠~e~t和活化熵△S^≠~e~t分别为1.2×10^2kJ·mol^-^1和5.0×10^2J·mol^-^1·K^-^1。在40℃, pH=8.0, Ⅰ=0.1mol·L^-^1,trans-[(en)~2(NO~2)Co(O~2CC~5H~4N)]^2^+/[Fe(CN)~5(H~2O)]^3^-反应体系前驱双核配合物分子内电子转移速率常数为7.0×10^-^5s^-^1。最后讨论了分子轨道对称性, 两金属中心氧化还原电势差等因素对电子转移速率的影响。  相似文献   

8.
郑丽敏  忻新泉  梅毓华 《化学学报》1991,49(12):1473-1477
本文用红外、紫外可见漫反射、X射线粉末衍射和四极质谱等实验手段,研究了四氰合镍酸钾一水合物与草酸、丙二酸、反丁烯二酸、丁二酸、己二酸的固相反应,发现K~2[Ni(CN)~4].H~2O与一些固体酸在室温下就发生反应,生成Ni(CN)~2.xH~2O,并放出HCN气体。由产物与反应物相对含量大小,得到固体有机酸的酸性强弱顺序为:草酸二水合物>丙二酸>反丁烯二酸>丁二酸>己二酸。讨论了可能的反应机制。  相似文献   

9.
张卫华  忻新泉 《化学学报》1996,54(4):368-373
本文研究室温下[Fe(bpy)3](ClO4)3.3H2O和[Fe(phen)3](ClO4)3.H2O分别与Na2S2O3.5H2O发生的固-固相氧化还原反应。用Mossbauer谱、XRD、IR、UV漫反射谱、元素分析、TG-DTA和磁化率测定等手段表征了反应24h后的固相产物,报道了[Fe(bpy)3](ClO4)2的结晶学数据。结果表明, 室温下反应速度快, 反应进行完全。  相似文献   

10.
本文用红外、紫外可见漫反射、X射线粉末衍射和四极质谱等实验手段,研究了四氰合镍酸钾一水合物与草酸、丙二酸、反丁烯二酸、丁二酸、己二酸的固相反应,发现K~2[Ni(CN)~4].H~2O与一些固体酸在室温下就发生反应,生成Ni(CN)~2.xH~2O,并放出HCN气体。由产物与反应物相对含量大小,得到固体有机酸的酸性强弱顺序为:草酸二水合物>丙二酸>反丁烯二酸>丁二酸>己二酸。讨论了可能的反应机制。  相似文献   

11.
A kinetic study of the hexacyanoferrate(III)-cyanide redox reaction has been made in connection with development of a new catalytic method for copper. The reaction kinetics change with time from first- to second-order dependence with respect to hexacyanoferrate(III). The reaction is nearly inverse first-order with respect to hexacyanoferrate(II) and first-order with respect to cyanide. The reaction shows a strong positive primary salt effect, but a very small increase in the reaction rate with temperature is found. A parallel reaction proceeds with a first-order dependence with respect to hydroxide. A tentative mechanism is proposed for the first reaction, involving the formation of cyanogen radicals. The second reaction corresponds to the well-known decomposition of hexacyanoferrate(III) in alkaline medium. The catalysed reaction exhibits similar kinetics with respect to hexacyanoferrate(II) and (III) but is zero-order with respect to cyanide and hydroxide and first-order with respect to catalyst. The proposed mechanism involves two consecutive interactions of the hexacyanoferrate(III) with copper(I) and with copper(II) cyanide complexes respectively, followed by a 2-electron oxidation of a co-ordinatively bridging cyanide group.  相似文献   

12.
A novel chemiluminescence (CL) flow-through sensor for the determination of pyrogallol has been developed. The method is based on the reaction between pyrogallol and potassium hexacyanoferrate(III) in sodium hydroxide solution. Potassium hexacyanoferrate(III) involved in the CL reaction was electrostatically immobilized on anion-exchange resin packed in a column. Pyrogallol was sensed by the CL reaction between pyrogallol and potassium hexacyanoferrate(III) which was eluted from the ion-exchange column through sodium phosphate injection. The CL emission allows quantitation of pyrogallol concentration in the range 0.01-3.8 microg/mL with a detection limit (3 sigma) of 0.003 microg/mL and a sample throughput of 118 h(-1). The relative standard deviation (n=7) was 2.2% for 0.2 microg/mL of pyrogallol. The influence of foreign compounds was tested.  相似文献   

13.
The electron-transfer reaction between bis(cyclopentadienyl)iron(II) ([Fe(II)(C5H5)2]) in nitrobenzene and a hexacyanoferrate redox couple ([Fe(II/III)(CN)6](4-/3-)) in water at the nitrobenzene / water interface was studied using normal pulse voltammetry. The voltammetric results indicate that the electron-transfer reaction takes place by way of a so-called ion-transfer (IT) mechanism, of which the forward and backward rate constants of the homogeneous electron-transfer reaction between [Fe(II/III)(C5H5)2](0/+) and [Fe(II/III)(CN)6](4-/3-) in the water phase have been determined. The electron-transfer reaction between [Fe(II)(C5H5)2] in 1,2-dichloroethane and [Fe(II/III)(CN)6](4-/3-) in water at the 1,2-dichloroethane / water interface was shown to also take place by the IT-mechanism.  相似文献   

14.
A kinetic study of the oxidation of allyl alcohol by potassium hexacyanoferrate (III) in the presence of palladium (II) chloride is reported. The reaction was observed by measuring the disappearance of the potassium hexacyanoferrate (III) spectrophotometrically. The reaction is first order with respect to allyl alcohol and palladium (II) chloride, inverse second order with respect to [Cl?], and zero order with respect to potassium hexacyanoferrate (III). The rate is found to increase linearly with hydroxyl ion concentration.  相似文献   

15.
Rao GG  Rukmini V 《Talanta》1967,14(7):849-851
The use of iron(III) in sulphuric acid medium and of potassium hexacyanoferrate(III) in hydrochloric acid medium has been investigated for the oxidimetric determination of indigo and indigo sulphonic acid. Conditions have been established for the assay of the dye with iron(III) sulphate at 100 degrees and with potassium hexacyanoferrate(III) at room temperature.  相似文献   

16.
Raman spectroscopy using a hot stage indicates that the intercalation of hexacyanoferrate(II) and (III) in the interlayer space of a Mg, Al hydrotalcites leads to layered solids where the intercalated species is both hexacyanoferrate(II) and (III). Raman spectroscopy shows that depending on the oxidation state of the initial hexacyanoferrate partial oxidation and reduction takes place upon intercalation. For the hexacyanoferrate(III) some partial reduction occurs during synthesis. The symmetry of the hexacyanoferrate decreases from Oh existing for the free anions to D3d in the hexacyanoferrate interlayered hydrotalcite complexes. Hot stage Raman spectroscopy reveals the oxidation of the hexacyanoferrate(II) to hexacyanoferrate(III) in the hydrotalcite interlayer with the removal of the cyanide anions above 250 °C. Thermal treatment causes the loss of CN ions through the observation of a band at 2080 cm−1. The hexacyanoferrate (III) interlayered Mg, Al hydrotalcites decomposes above 150 °C.  相似文献   

17.
本文首次报道了铁氰化钾在室温下与碘化钾、硫化钾的固相氧化还原反应,实验发现在固相下铁氰化钾与碘化钾混合后,生成单质碘和亚铁氰化钾,而在溶液中该反应是反方向进行的.实验还发现,在固相下铁氰化钾与还原剂硼氢化钠不反应,而在溶液中,该反应却能进行.对反应机制进行了初步探讨.  相似文献   

18.
本文首次报道了铁氰化钾在室温下与碘化钾、硫化钾的固相氧化还原反应,实验发现在固相下铁氰化钾与碘化钾混合后,生成单质碘和亚铁氰化钾,而在溶液中该反应是反方向进行的.实验还发现,在固相下铁氰化钾与还原剂硼氢化钠不反应,而在溶液中,该反应却能进行.对反应机制进行了初步探讨.  相似文献   

19.
The Yb(II) hydride complex (DIPP-nacnac)YbH x THF (3-Yb, DIPP-nacnac = CH{(CMe)(2,6-iPr(2)C(6)H(3)N)}(2)) was prepared by a mild metathesis reaction of (DIPP-nacnac)Yb[N(SiMe(3))(2)].THF with PhSiH(3). 3-Yb crystallizes as a dimer with bridging hydride ions, and its geometry is similar to that of the analogue calcium hydride complex (3-Ca). 3-Yb is well soluble in benzene and remarkably stable in solution at room temperature. Ligand exchange to the homoleptic Yb(II) complexes takes place at higher temperatures (3-Yb is less stable than the analogue 3-Ca). The soluble hydride complexes 3-Ca and 3-Yb are catalysts for the hydrosilylation of 1,1-diphenylethylene, but differences in the product distributions are observed. Slow hydrolysis of (DIPP-nacnac)Yb[N(SiMe(3))(2)].THF gave reduction of water and unidentified Yb(III) complexes. Fast hydrolysis at low temperature, however, resulted in the first Yb(II) hydroxide complex, (DIPP-nacnac)Yb(OH) x THF (4-Yb, 20% yield), which is a dimer with bridging hydroxide ions in the solid state. The crystal structure is isomorphous to that of the calcium analogue 4-Ca. 4-Yb is well soluble in benzene and considerably more stable against ligand exchange and formation of homoleptic species than 3-Yb.  相似文献   

20.
用气相色谱法研究了草酸铁(Ⅲ)与路易氏碱在氢气氛和氦气氛中的固相反应。结果表明草酸铁与氢氧化钠在室温下明显发生固相反应,其产物随温度升高而变化。同时发现α-Fe对草酸钠有催化分解作用,与四硫化钾低于220°C时发生固相反应,生成KFeS2,但只有1/4草酸铁参加了固相反应,反应不完全,对固相反应的机制及反应气氛的影响也进行了探讨。  相似文献   

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