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1.
荧光指示剂载体对荧光法溶氧传感器荧光膜性能的影响   总被引:1,自引:0,他引:1  
以沉淀白炭黑、气相白炭黑和MQ树脂负载荧光指示剂Ru(dpp)3Cl2,添加到二甲基硅橡胶,制备氧敏感荧光膜,研究指示剂载体和用量对荧光膜荧光输出的影响。结果表明:纯硅橡胶荧光膜的荧光输出很低,SiO2填料可作荧光指示剂的载体提高指示剂的分散和荧光效率,SiO2填料提高荧光效率的能力为MQ树脂>气相白炭黑>沉淀白炭黑。含10%SiO2载体的硅橡胶制备的荧光膜,其荧光输出随指示剂用量线性增加,直至指示剂用量达0.1%,但SiO2填料降低荧光膜的响应速度。  相似文献   

2.
为减少荧光指示剂被水萃取流失,提高荧光膜的使用寿命,将5-氨基-邻菲咯啉与二(4,7-二苯基-邻菲咯啉)二氯化钌(Ⅱ)络合,合成带氨基的荧光指示剂[Ru(dpp)2(phen-NH2)]Cl2,并经氨基键合到有机玻璃表面。以核磁、质谱、红外验证合成荧光指示剂的结构,研究键合条件对染色有机玻璃荧光发射的影响,监测荧光强度随水浸泡时间的变化。合成荧光指示剂的荧光发射峰值波长为570 nm,键合到有机玻璃后发射光谱红移20 nm,荧光强度受溶解氧影响,响应时间约为10 s,氧猝灭比达4。染色有机玻璃的荧光稳定性好,在50 ℃水中浸泡7个月,荧光强度下降小于1%。  相似文献   

3.
罗峰 《分析科学学报》2011,27(2):175-178
选用3,3,3-三氟丙基三甲氧基硅烷为前驱体,制备氧光化学传感膜材料.利用4,7-二苯基-1,10-邻菲咯啉钌(Ⅱ)([Ru(dpp)3(ClO4)2])为氧荧光猝灭指示剂,通过优化制备条件获得对氧浓度变化具有敏感响应的传感膜.研究结果表明:所制备的氧传感膜对水体中的溶解氧的线性响应范围为0.5~16.0 mg/L,最...  相似文献   

4.
顾强  邹爱华  王永  袁春伟 《化学学报》2004,62(2):131-136
用sol-gel法以正硅酸乙酯、乙醇和蒸馏水为原料,以盐酸为催化剂,包埋三联吡啶钌[Ru(bpy)3Cl2]制备催化 Belousov-Zhabotinsky (BZ)反应的非线性光催化薄膜,并利用紫外分光光度法测定了在薄膜中Ru(bpy)3Cl2的包埋量.通过投影图像的方法光激发BZ反应,在包埋Ru(bpy)3Cl2的薄膜上产生化学波图像.在薄膜中演化形成的图像具有相当高的图像清晰度.在图像的演化过程中,具有图像反转、边界增强、图像分割等图像处理能力,并可以通过改变BZ反应条件来调控增强某些图像处理能力.  相似文献   

5.
研究了在室温离子液体以及室温离子液体/有机溶剂复合介质体系中, Rh(PPh3)3Cl, Ru(PPh3)3Cl2等催化烯烃与三乙氧基硅烷的硅氢加成反应. 实验结果表明, 在乙二醇二甲醚/离子液体1-丁基-3-甲基咪唑六氟磷酸盐(BMImBF6) (V/V=1/4)介质中, 于90 ℃下, 己烯与三乙氧基硅烷反应的转化率为100%, β加成物的选择性可达89.0%. 而用Rh(PPh3)3Cl作为反应的催化剂, 在纯离子液体BMImPF6中, 就可以高效催化烯烃与三乙氧基氢硅烷的加成反应. 过渡金属Rh(PPh3)3Cl, Ru(PPh3)3Cl2催化剂/离子液体BMImPF6催化体系, 不仅解决了产物与催化剂分离困难这一难题, 同时, 离子液体BMImPF6的存在提高了过渡金属Rh(PPh3)3Cl, Ru(PPh3)3Cl2催化硅氢加成反应的活性, 特别是β加成物的选择性. 反应结束后, 催化剂/离子液体与产物易于分离, 并且可以重复使用.  相似文献   

6.
研究了5种钯配合物Pd(bipy)Cl2, Pd(phen)Cl2, [Pd(dien)Cl]Cl, trans-Pd(NH3)2Cl2和cis-Pd(NH3)2Cl2对结核杆菌RecA intein蛋白质剪接的抑制作用. 结果表明, trans-Pd(NH3)2Cl2的抑制活性最好, IC50=3.3×10-5 mol/L. 钯配合物通过与intein的第一个氨基酸(半胱氨酸)配位, 从而抑制蛋白质的剪接活性. 荧光猝灭的动力学数据表明, 配体的大小会明显影响钯配合物与intein的相互作用, 配体越大, 作用越慢.  相似文献   

7.
为使不对称Ru-Fe化合物能在表面上自组装形成单分子膜,对trans-RuCl(dppm)2(C≡CFc)[Fc=C5H4FeC5H5,dppm=(C6H5)2PCH2P(C6H5)2](1)进行修饰,得到Ru(dppm)2(C≡CFc)(C≡CPhOCH3)(2),[Ru(dppm)2(C≡CFc)(N≡CCH2CH2NH2)][PF6](3)和[Ru(dppm)2(C≡CFc)(N≡CCH2CH2NHC(O)·(CH2)10SH)][PF6](4),并详细研究了该系列化合物的电化学性质.循环伏安结果显示出Ru周围配体得失电子能力的差别,直接影响了Ru中心的氧化-还原性,但这种影响并没有通过共轭的炔键传递到二茂铁中的Fe中心.化合物4可以在Au表面上自组装形成稳定、有序的单分子膜.还利用循环伏安法研究了单分子膜的形成过程及其表面覆盖率.  相似文献   

8.
我们在此报道了一种未曾发现的有趣现象:尽管[Au23(SC6H11)16]、Au24(SC2H4Ph)20 (Ph:苯环)、Au36(TBBT)28 (TBBTH:对叔丁基苯硫酚)、Au38(SC2H4Ph)24、混合Aux(SC2H4Ph)y团簇及3 nm的金纳米粒子有不同的组成、结构、尺寸和保护性硫醇配体,但它们在三苯基膦(PPh3)作用下,均能统一地经由亚稳的[Au11(PPh3)8Cl2]2+最终转化为稳定的双二十面体[Au25(PPh3)10(SR)5Cl2]2+ (SR:硫醇配体)。换句话说,三苯基膦是这些硫醇保护的纳米粒子的统一转化器。然而,聚乙烯吡咯烷酮(PVP)/柠檬酸盐(Citrate)保护的金纳米粒子和[Ag25(SPhMe2)18] (Me:甲基)在同样的条件下,却不能转化为[Au25(PPh3)10(SR)5Cl2]2+或[Ag25(PPh3)10(SR)5Cl2]2+,暗示了硫醇保护的金纳米粒子具有与三苯基膦反应的独特性能。另外,我们考察了配体对双二十面体[Au25(PPh3)10(SR)5Cl2]2+团簇荧光性能的影响。  相似文献   

9.
合成了3种具有不同取代基的咪唑[4, 5-f]-1,10-邻菲罗啉配体L1~L3及其Ru(Ⅱ)配合物[Ru(L1)3]、[Ru(L2)3]和[Ru(L3)3],并进行了表征。这些Ru(Ⅱ)配合物在溶液中具有π→π*跃迁吸收峰和金属到配体的电荷转移跃迁(MLCT)吸收峰,其发光峰位约为590 nm左右。将Ru(Ⅱ)配合物掺杂到聚甲基丙烯酸甲酯(PMMA)中得到相应的温敏漆。Ru(Ⅱ)配合物在PMMA膜中的吸收峰精细结构消失,且在长波方向663 nm附近有新的发射峰,表明Ru(Ⅱ)配合物在PMMA膜中有聚集。温度升高后,Ru(Ⅱ)配合物在PMMA膜中的发射峰强度逐渐减弱。分别计算了在30~60 ℃和60~90 ℃区间内非辐射活化能Enr和温度灵敏度ST。结果表明,具有苯基取代的咪唑[4, 5-f]-1,10-邻菲罗啉配体的[Ru(L1)3]配合物,比咪唑[4, 5-f]-1,10-邻菲罗啉Ru(Ⅱ)配合物[Ru(L2)3]及烷基取代基的咪唑[4, 5-f]-1,10-邻菲罗啉Ru(Ⅱ)配合物[Ru(L3)3]具有更高的温度灵敏度。  相似文献   

10.
了解金属纳米团簇的形成机制对于进一步发展其化学制备方法是必要的。我们利用盐酸(HCl)和十二硫醇(RSH)共同刻蚀L3 (L3: 1, 3-双二苯基膦丙烷)包覆的多分散性的Aun (15 ≤ n ≤ 60)团簇成功制备出单分散性的Au13(L3)2(SR)4Cl4纳米团簇,并结合原位同步辐射X射线吸收谱、原位真空紫外-可见吸收光谱和质谱技术,研究了Au13(L3)2(SR)4Cl4纳米团簇的动力学形成过程。结果表明,Au团簇从多分散到单分散的转变经历了3个明显不同的动力学步骤。首先,尺寸较大的多分散金属团簇Aun主要在HCl刻蚀作用下,形成尺寸较小的亚稳的中间产物Au8–Au11团簇。然后,这些中间产物与反应溶液中已有的Au(Ⅰ)-Cl物种反应,并与SR发生部分配体交换,逐渐长大为由SR和L3保护的Au13团簇。最后,形成的Au13团簇经过一个较缓慢的结构重组过程,最终形成稳定的Au13(L3)2(SR)4Cl4的纳米团簇。  相似文献   

11.
The reaction of the dimer complex [{Ru(CO)3Cl2}2] with the ligands 4,6-dichloroquinoline-5,8-dione and 6-methoxybenzo[g]quinoline-5,10-dione in ethanol solution led to the neutral mononuclear complexes of general formula [Ru(CO)2Cl22-quinolinedione-N,O)]. The complexes were characterized by elemental analysis, IR and RMN spectroscopy, and the molecular structure of [Ru(CO)2Cl2(6-methoxybenzo[g]quinoline-5,10-dione)] was determined by single-crystal X-ray diffraction. The redox chemistry of ligands and complexes was investigated by cyclic voltammetry, and their potential antitumor activity was also evaluated.  相似文献   

12.
Ru(II)-complex functionalized silica nanoparticles(nano-SiO2) were prepared via a coordination reaction of cis-dichlorobis(2,2'-bipyridine)ruthenium[Ru(bpy)2Cl2] complex with poly(4-vinylpyridine)(P4VP)-modified nano-SiO2 particles. Both the Ru-complex and the functionalized nano-SiO2P4VP-Ru(bpy) hybrids were doped in poly(methyl methacrylate)(PMMA) to form optically transparent thin films. The composition and spectroscopic properties of the nano-SiO2P4VP-Ru(bpy) hybrids were evaluated with the help of thermogravimetric and elemental analysis, and UV-Vis absorption spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and fluorescence spectroscopy. Microscopy images revealed that the nanohybrids were approximately 12 nm in diameter and readily formed aggregates following the functionalization with P4VP and Ru(bpy)2Cl2. The as-prepared nano-SiO2P4VP-Ru(bpy) hybrids produced emissions at approximately 604 and 654 nm under radiation both in solution and in doped thin films. Finally, cyclic voltammetry studies on the nanohybrid-modified electrode revealed a redox couple with the cathodic and anodic potentials at approximately 0.28 and 0.73 V(vs. Ag/AgCl), attributed to the one electron transfer of Ru(bpy)22+/3+ immobilized on the nano-SiO2 particles.  相似文献   

13.
The mononuclear chelated complex [RuCl(Cp)(η2-dppa)] has been synthesised and reacted with [Rh2Cl2(CO)4] to form the heterobimetallic complex [(Cp)Ru(μ-CO)2{(μ-Ph2PN(H)PPh2}RhCl2]. Complexes of [RuCl(Cp){(PPh2)2CHCH2PPh2}] have been reacted with [Rh2Cl2(CO)4] or [RhCl(CO)2(p-toluidene)]. Characterisation of these new ruthenium complexes was carried out using 31P-NMR, FAB mass spectroscopy, elemental analysis and IR spectrophotometry.  相似文献   

14.
The reaction of Ru(CO)4(C2H4) or Ru(CO)5 with 1,5-Ph4P2N4S2 in CH2Cl2/hexane at 23°C produces the dimer [Ru(CO)2(Ph4 P2N4S2)]2 (2), which was shown by X-ray crystallography to have a centrosymmetric structure in which the P2N4S2 ring is attached to one ruthenium atom through two (geminal) nitrogen atoms and the remote sulfur atom and serves as a bridge to the other ruthenium atom via the second sulfur atom. Crystals of 2 ·2(CH2Cl2) are triclinic, space group P (No. 2), a = 12.901(1) Å, b = 13.072(1) Å, c = 10.123(1) Å, = 100.88(1)°, β = 98.90(1)°, γ = 67.50(1)°, V = 1542.4(3) Å, Z = 1 with final R and Rw values of 0.040 and 0.027, respectively.  相似文献   

15.
Sn(CH3)2Cl2 exerts its antitumor activity in a specific way. Unlike anticancer cis-Pt(NH3)2Cl2 drug which binds strongly to the nitrogen atoms of DNA bases, Sn(CH3)2Cl2 shows no major affinity towards base binding. Thus, the mechanism of action by which tinorganometallic compounds exert antitumor activity would be different from that of the cisplatin drug. The aim of this study was to examine the binding of Sn(CH3)2Cl2 with calf thymus DNA and yeast RNA in aqueous solutions at pH 7.1–6.6 with constant concentrations of DNA and RNA and various molar ratios of Sn(CH3)2Cl2/DNA (phosphate) and Sn(CH3)2Cl2/RNA of 1/40, 1/20, 1/10, 1/5. Fourier transform infrared (FTIR) and UV–visible difference spectroscopic methods were used to determine the Sn(CH3)2Cl2 binding mode, binding constant, sequence selectivity and structural variations of Sn(CH3)2Cl2/DNA and Sn(CH3)2Cl2/RNA complexes in aqueous solution. Sn(CH3)2Cl2 hydrolyzes in water to give Sn(CH3)2(OH)2 and [Sn(CH3)2(OH)(H2O)n]+ species. Spectroscopic evidence showed that interaction occurred mainly through (CH3)2Sn(IV) hydroxide and polynucleotide backbone phosphate group with overall binding constant of K(Sn(CH3)2Cl2–DNA)=1.47×105 M−1 and K(Sn(CH3)2Cl2–RNA)=7.33×105 M−1. Sn(CH3)2Cl2 induced no biopolymer conformational changes with DNA remaining in the B-family structure and RNA in A-conformation upon drug complexation.  相似文献   

16.
Synthesis and catalytic properties of a series of ruthenium carbonyl complexes with 2-substituted pyrazine ligands (pz–R; R = Cl, OMe, SMe, CN, NH2) have been studied. Reactions between the [Ru(CO)3Cl2]2 and the pyrazines led mainly to mononuclear compounds of the type [Ru(CO)3Cl2(R–pz)]. All of these ruthenium pyrazine compounds showed activity in 1-hexene hydroformylation. With an exception of NH2, addition of the substituent to the pyrazine ring was found to improve the catalytic activity compared to the unsubstituted pyrazine. The catalytic cycle was studied by computational DFT methods. The results suggest that the key step in the formation of the active species involves release of one of the carbonyl in the cis position with respect to the pyrazine ring.  相似文献   

17.
The generality of a two-electron reduction process involving an mechanism has been established for M3(CO)12 and M3(CO)12n(PPh3)n (M = Ru, Os) clusters in all solvents. Detailed coulometric and spectral studies in CH2Cl2 provide strong evidence for the formation of an ‘opened’ M3(CO)122− species the triangulo radical anions M3(CO)12−· having a half-life of < 10−6 s in CH2Cl2. However, the electrochemical response is sensitive to the presence of water and is concentration dependent. An electrochemical response for “opened” M3(CO)122− is only detected at low concentrations < 5 × 10−4 mol dm−3 and under drybox conditions. The electroactive species ground at higher concentrations and in the presence of water M3(CO)112− and M6(CO)182− were confirmed by a study of the electrochemistry of these anions in CH2Cl2; HM3(CO)11 is not a product. The couple [M6(CO)18]−/2− is chemically reversible under certain conditions but oxidation of HM3(CO)11 is chemically irreversible. Different electrochemical behaviour for Ru3(CO)12 is found when [PPN][X] (X = OAc, Cl) salts are supporting electrolytes. In these solutions formation of the ultimate electroactive species [μ-C(O)XRu3(CO)10] at the electrode is stopped under CO or at low temperatures but Ru3(CO)12−· is still trapped by reversible attack by X presumably as [η1-C(O)XRu3(CO)11]. It is shown that electrode-initiated electron catalysed substitution of M3(CO)12 only takes place on the electrochemical timescale when M = Ru, but it is slow, inefficient and non-selective, whereas BPK-initiated nucleophilic substitution of Ru3(CO)12 is only specific and fast in ether solvents particulary THF. Metal---metal bond cleavage is the most important influence on the rate and specificity of catalytic substitution by electron or [PPN]-initiation. The redox chemistry of M3(CO)12 clusters (M = Fe, Ru, Os) is a consequence of the relative rates of metal---metal bond dissociation, metal-metal bond strength and ligand dissociation and in many aspects resembles their photochemistry.  相似文献   

18.
The compound [Ru2(μ-O2CCH3)4(THF)2]BF4 (I) containing the Ru25+ unit was prepared by reaction of Ru2Cl(μ-O2CCH3)4 with AgBF4 in THF. This compound, in contrast with Ru2Cl(μ-O2CCH3)4, is soluble in several polar organic solvents and reacts in THF with OPPh3 and PPh3 giving [Ru2(μ-O2CCH3)4(OPPh3)2]BF4·CH2Cl2 (II) and [Ru(μ-O2CCH3)(O2CCH3)(PPh3)]n (III), respectively. The complex II has been also obtained as hexafluorophosphate [Ru2(μ-O2CCH3)4(OPPh32]PF6·CH2Cl2 (IV) by treatment of Ru2Cl(μ-O2CCH3)4 with an excess of NOPF6 and PPh3 in methanol. In this reaction the triphenylphosphine oxide is generated by oxidation of the triphenylphosphine.  相似文献   

19.
Ru(bpy)33+, which is important in artificial photosynthetic systems due to its high reduction potential, is stabilized together with its counter anion, Ru(bpy)3+, by radiolysis of Ru(bpy)32+ adsorbed on silica gel at 77 K. Both species are characterized by electron spin resonance.  相似文献   

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