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1.
Stable and well-dispersed poly(N-vinyl-2-pyrrolidone) (PVP)-stabilized ruthenium colloidal clusters wereprepaxed via the reduction of ruthenium(III) chloride by refluxing with low boiling point alcohols. Investigation of the size ofRu colloids by transmission electron microscopy (TEM) indicated that the average diametes could be controlled in the rangeof 1.2-1.6 nm with relative standard deviations of less than 0.33 by changing the molar ratio of PVP to Ru. The X-rayphotoelectron spectroscopy (XPS) characterization verified the formation of elemental ruthenium colloids. 相似文献
2.
FengSHI HongYangLI XiaoJunPENG RongZHANG XiaoQiangCHEN JiangLiFAN LiChengSUN 《中国化学快报》2004,15(12):1407-1410
As photosensitizer for solar cell, a new ruthenium (Ⅱ) complex with four ester groups had been synthesized, in which a phenol substituted by {[(2-hydroxy-5-tert-butylbenzyl)(pyridyl-2-methyl)amino]methyl} is covalently linked to ruthenium (Ⅱ) tris-bipyridine. The structures of the new compounds were confirmed by NMR and ESI-MS spectra. The electrochemical and photochemical properties were also studied. 相似文献
3.
The cobalt and ruthenium bimetallic complex of poly-γ-amino-propylsiloxane( abbr. as Si-CH_2-Co-Ru) was prepared, and it was found that it can catalyze the hydroformylation of cyclobexene effectively with the conversion amounting to over 90%. Cyclohexanecarboxaldehyde was first formed in the hydroformylation, and then further hydrogenated to form cylcohexanemethanol. The coversion was affected obviously by the Co/Ru ratio.When Co/Ru molar ratio was 100-150, i.e. in the very low content of noble metal Ru, the catalytic activity of Si-NH_2 -Co-Ru was also very high. The product composition was affected by CO/H_2 ratio in the reaction gas. Aldehyde can be got high selectively by controlling CO/H_2 ratio. Compared with other catalyst system, the Si-NH_2-Co-Ru catalyst has higher catalytic activity and efficiency with very low Ru/Co ratio. The total turnover number was more than 28,800 (based on the amount of ruthenium used). 相似文献
4.
<正>Poly(N-vinyl-2-pyrrolidone)(PVP)-stabilized ruthenium nanorods with high aspect ratio by refluxing ruthenium(Ⅲ) chloride in n-propanol have been successfully prepared by means of a facile and rapid microwave heating for the first time.The structure and morphology of the obtained products were characterized by transmission electron microscopy(TEM),select area electron diffraction(SAED),ultraviolet-visible spectrophotometry(UV-vis),X-ray photoelectron spectroscopy(XPS) and Fourier transform spectroscopy(FT-IR).XPS analysis reveals that the nanorods were in the metallic state.TEM images showed that ruthenium nanorods had an obvious one-dimensional structure with the aspect ratio ranged from 5 to 40 nm and length up to 600 nm.SAED patterns indicated that the nanorods were single-crystalline with a hexagonal structure. 相似文献
5.
Polymer LB films containing photofuntional groups were prepared by the copolymerization of N-dodecylacrylamide (DDA), which has an excellent property to form a stable monolayer and LB multilayerswith photofunctional monomers. Tris(2, 2'-bipyridine) ruthenium complex, Ru(bpy)_3~(2+), one of the most well-known redox-active sensitizer, was incorporated into the DDA copolymer. The photogalvanic effect based onthe photoinduced electron transfer using the ruthenium complex in the polymer LB monolayer was discussed. 相似文献
6.
《结构化学》2017,(11)
Three half-sandwich ruthenium(II) p-cymene complexes containing naphthalenebased Schiff base ligands [Ru(p-cymene)LCl](2 a~2 c) have been synthesized and characterized. Both Schiff-base ligands and ruthenium complexes were fully characterized by ~1H and ~(13)C NMR spectra, mass spectrometry and infrared spectrometry. The molecular structure of ruthenium complex 2 b was confirmed by single-crystal X-ray diffraction methods. For the complex: C_(24_H_(23)ClN_2ORu, M_r = 524.02, monoclinic, space group P21/c, a = 12.3888(4), b = 17.3296(6), c = 20.7744(7) ?, β = 92.8000(10)°, V = 4454.8(3) ?~3, Z = 8, Dc = 1.563 g/cm~3, μ = 0.936 mm~(-1), F(000) = 2128, S = 1.154, the final R = 0.0309 and w R = 0.0703. Moreover, these ruthenium complexes are active catalysts for the hydrogenation of nitroarenes to aromatic anilines in the presence of sodium tetrahydroborate(NaBH_4) reducing agent. 相似文献
7.
Two new mixed-ligand ruthenium(Ⅱ) complexes,Ru(dcbpy)-(LL)NCS)2[where dcbpy=4,4‘-dicarboxyl-2,2‘‘-bipyridine,LL=4,4‘-bis(N-methyl-anilinomethyl)-2,2‘‘-bipyridine(2)],were synthesized,and the tphotophysical properties of these complexes were studied.The metal-to-ligand charge transfer (MLCT) transitions of these complexes exhibited solvatochromic effect due to the existence of NCS ligands.The MLCT energies also strongly depend on the pH values of the solutions because of protonation and deprotonation of the carboxyl groups.The pKa values of the ground state,4.0 for 1 and 3.8 for 2,were obtained from the titration curves.The photoelectrochemical properties of 1 and 2 as sensitizers in sandwich-type solar cells have been studied.Complex 1 exhibited better photoelectrochemical behavior than complex 2 as expected.It was proved that the design of mixed-ligand complex by introducing electron donating group in one of the ligands should be a promising approach. 相似文献
8.
TANG Duihai ;ZHANG Weiran WANG Yifan MIAO Jing QIAO Zhen'an HUO Qisheng ZHANG Lirong 《高等学校化学研究》2014,30(4):531-537
A series of functional mesoporous silica nanoparticles(MSNs) was synthesized by a one-step simple synthesis approach involving co-condensation of tetraethoxysilane(TEOS) and salicylaldimine ligand(Sal-Si) in the presence of cetyltrimethylammonium chloride(CTAC) under basic conditions.The target MSNs with different sizes (50,100 and 200 nm,respectively) were obtained.Furthermore,the Ca^2+ cations were also introduced into MSNs.The prepared nanoparticles were characterized by means of infrared(IR) spectra,thermogravimetric analysis(TGA),inductively coupled plasma(ICP),CHN elemental analysis,nitrogen adsorption-desorption,scanning electron microscope(SEM) and transmission electron microscope(TEM).Ibuprofen(IBU) which contains carboxyl groups was selected as a model drug.The results of drug loading and release reveal that the loading capacities and release behaviors of the model drug are highly dependent on the Ca^2+ cations in MSNs.The release of IBU from the MSNs functionalized by Ca^2+ cations is found to be effectively controlled when compared to the release from the MSNs without the functionalization of Ca^2+ cations,which is due to the ionic interaction between carboxyl groups in IBU and Ca^2+ cations in MSNs. 相似文献
9.
[Ru(bpy)3]2+/MCM-41 composite material obtained by loading tris(2,2′-bipyridine)ruthenium(Ⅱ)([Ru(bpy)3]2+) in siliceous mesoporous MCM-41 was characterized by X-ray powder diffraction, UV-Vis absorption and emission spectroscopies. The absorption spectrum of [Ru(bpy)3]2+/MCM-41 is similar to that of [Ru(bpy)3]2+ aqueous solution, whereas its emission spectrum exhibits hypsochromic shift compared to the solution spectrum. On the other hand, the peak position of the emission spectrum of [Ru(bpy)3]2+/MCM-41 shifts towards longer wavelength when the loading amount increases. 相似文献
10.
LIYan-yun CHENJian-shan YANGChuan-bo DONGZhen-rong LIBao-zhu ZHANGHui GAOJing-xing TAKAOIkariya 《高等学校化学研究》2004,20(2):180-184
The efficient chiral Ru3(CO)12 systems were prepared in situ from Ru3(CO)12 and various chiral diiminoor diamino-diphosphine tetradentate ligands. The systems have been used for the asymmetric transfer hydrogenation of propiophenone in 2-propanol, leading to 1-phenyl-1-propanol in a 98% yield and 96% e.e. The IR study suggests that the carbonyl hydride anion [HRu3(CO)11]^- most probably exists as a principal species under the reaction conditions. The high chiral efficiency may be due to the synergetic effect produced by the neighboring ruthenium atoms and a special chiral micro-environment involving the polydentate ligand and the Ru3 framework. 相似文献
11.
为探讨急性心肌梗死(AMI)患者血清中K+、Na+、Ca2+、Fe2+、Mg2+含量变化,并研究其与心肌梗死患者之间的关系。选取2022年5月至2023年2月收治的AMI患者37例,同时选取健康体检者35例作为对照组。依据入院时或体检时收集的抽血样本进行临床生化分析,比较两组间血清K+、Na+、Ca2+、Fe2+、Mg2+含量,采用判别方程、主成分分析法(PCA),判断分析哪种金属离子对于心肌梗死的诊断价值大。结果表明,AMI患者的血清中Ca2+和Fe2+含量低于健康对照组,差异具有统计学意义。基于血钙、铁水平两组具有显著性差异,以它们为基础进行判别分析,获得判别函数式。将血清中K+、Na+、Ca2+、Fe2+、Mg2+ 相似文献
12.
For M?H2O (M = Mg, Mg+, Mg2+, Ca, Ca+, Ca2+) various energy contributions (first-order, induction and charge-transfer, dispersion) are compared. Near the minimum, stability due to the first-order energy decreases and that due to dispersion increases from M2+ to M0. For M2+, dispersion represents only 1–7% of the total energy; it may reach 25% with M+ and is largely responsible for stability of the neutral complex. 相似文献
13.
V. V. Yanilkin N. V. Nastapova A. S. Stepanov A. A. Kalinin V. A. Mamedov 《Russian Chemical Bulletin》2009,58(1):89-94
The binding of cations Li+, Na+, K+, Cs+, Ag+, Zn2+, Ni2+, Co2+, NH4
+ (group I), H+, Mg2+, Al3+, Ga3+ (group II), and Ca2+, Pb2+ (group III) by 21,31-diphenyl-l 2,42-dioxo- 7,10,13-trioxa-l,4(3,1)-diquinoxalina-2(2,3),3(3,2)-diindolizinacyclopentadecaphane (1), which contains two indolizine and two quinoxaline fragments and 3,6,9-trioxaundecanes spacer, and by its acyclic analog
(2) was studied using cyclic voltammetry in MeCN/0.1 M Bu4NBF4. It was concluded that the ions of group I are not bound by these compounds, the ions of group II exhibit the reversible
redox-switched binding by the carbamoyl groups of the quinoxaline fragments, whereas the ions of group III are bound not only
by the initial compounds and radical cations 1 and 2, but also by dication 1. This binding of the Ca2+ and Pb2+ ions stabilizes dication 1. 相似文献
14.
Angela F. Danil De Namor Walther B. Aparicio-Aragon Maria Teresa Goitia Alberto R. Casal 《Supramolecular chemistry》2013,25(6):423-433
The synthesis and characterization (1H and 13C NMR) of a partially substituted lower rim p-tert-butylcalix(4)arene, namely, 5,11,17,23-tetra-4-tert-butyl-25,27-bis(diethylphosphate amino)ethoxy-26,28-dihydroxycalix[4]arene (1), are reported. The solution thermodynamics of the ligand in a variety of solvents at 298.15?K was investigated through solubility (hence standard Gibbs energy of solution) measurements while the calorimetric technique was used to derive the standard solution enthalpy. These data were used to calculate the standard entropy of solution. An enthalpy–entropy compensation effect is shown and, as a result, slight variations are observed in the transfer Gibbs energies of this ligand from the reference to other solvents. 1H NMR, conductance and calorimetric measurements were carried out to establish the degree of interaction of the ligand with univalent (Li+, Na+, K+, Rb+, Cs+ and Ag+) and bivalent (Mg2+, Ca2+, Sr2+, Ba2+, Pb2+, Cd2+, Hg2+, Cu2+, Zn2+) cations in acetonitrile, methanol, N,N-dimethylformamide and propylene carbonate. No complexation was found between this ligand and univalent cations in these solvents. As far as the bivalent cations are concerned, interaction between 1 and these cations was found only in acetonitrile. The versatile behaviour of this ligand with bivalent cations in this solvent is reflected by the formation of complexes of different stoichiometry. Thus the interaction of 1 with alkaline-earth (Mg2+, Ca2+, Sr2+, Ba2+) and Pb2+ metal cations leads to the formation of 1:2 (cation:ligand) complexes. However, for other bivalent metal cations (Cu2+, Zn2+, Cd2+ and Hg2+) the complex stoichiometry was found to be 1:1. The results are discussed in terms of the key role played by acetonitrile in processes involving calix[4]arene derivatives. 相似文献
15.
16.
Najah Cheriaa Rym Abidi Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):303-312
Four imidazolyl acetamido p-tert-butylcalix[4]arenes 5–8 have been prepared by reacting the corresponding methyl esters derivatives 1–4 with histamine in 1:1 mixture of methanol:toluene. The yields ranged from 56 to 68%. 5–8 have been shown to be in cone conformation. The complexation behaviour of 5–8 towards monovalent metal picrates M+Pic− with M+ = Li+, Na+, K+, Rb+ and Cs+ and divalent metal picrates M2+(Pic−)2 with M2+ = Mg2+, Ca2+, Sr2+, Ba2+, Pb2+, Cd2+, Zn2+ and Co2+ are given. Tentative localisation of the metal cations in the receptors is given. The binding properties towards these cations
have been determined along with stoichiometries of the complexes. 相似文献
17.
The B3LYP/6-311++G (d,p) density functional approach was used to study the gas-phase metal affinities of Guanosine (ribonucleoside)
for the Li+, Na+, K+, Mg2+, Ca2+, Zn2+, and Cu+ cations. In this study we determine coordination geometries, binding strength, absolute metal ion affinities, and free energies
for the most stable products. We have also compared the results for Guanosine, with our previously reported results for 2′-Deoxyguanosine.
Based on the results, it is obvious that MIA is strongly dependent on the charge-to-size ratio of the cation. Guanosine interacts
more strongly with Zn2+ than do with Mg2+, Ca2+, and Cu+ and therefore stronger interactions lead to higher MIA. In both free molecules and their complexes, the Syn orientation of
the base is stabilized by an intramolecular O5′–H···N3 hydrogen bond and the anti orientation of the base is stabilized by
an intramolecular C–H···O hydrogen bond formed between the (C8-H8) and the O5′ atom of the sugar moiety. It is also interesting
to mention that linear correlation between calculated MIA values and the atomic numbers (Z) of the metal ions of Li+, Na+, and K+ were found. Furthermore, the influences of metal cationization on the strength of the N-glycosidic bond, torsion angles,
angle of pseudorotation (P), and intramolecular C–H···O and O–H···O hydrogen bonds have been studied. Natural bond orbital (NBO) analysis was performed
to calculate the charge transfer and natural population analysis of the complexes. Quantum theory of atoms in molecules (QTAIM)
was also applied to determine the nature of interactions. 相似文献
18.
N-Tosyl-2,6-diisopropyl-4-(2,3-dimethoxylbenzoylamide)aniline (1) has been synthesized and its metal ion (Na+, K+, Ca2+, Mg2+) coordinating properties investigated by FT-IR, ESI-MS, and 1H NMR methods. Among the tested metal ions, the overall stability constant (log K) for Mg2+ (6.89) is the highest (Na+, 5.64; K+, 5.43; Ca2+, 5.51) in 10% water/THF at 25.0 ± 0.5 °C determined by UV-vis spectroscopy, indicating that 1 is a potent ionophore for Mg2+ ion. 相似文献
19.
Shigeru Ikuta 《Chemical physics》1985,95(2):235-242
The most stable conformation of ion-molecule complexes involving a CO molecule were surveyed by the use of Hartree-Fock (HF) MO and third-order Moller-Plesset perturbation (MP3) methods with a 6–31G* basis set ion = H+, Li+, Na+, K+, Bc2+, Mg2+, and Ca2+. The MP3 level of theory reveals the ion-CO conformation in which the ion bonds to a carbon atom of CO to be the most stable; these MP3 results are contrary to the HF ones. Binding energies of ion-molecule complexes involving CO and N2 were computed; MP3 energies are in good agreement with the experimental ones. The computed binding energies of cation-N2 are about one-third of cation-NH3 due to the absence of dipole moment and the smaller polarizability of N2. The decrease in binding energy in cation-CO and -N2 complexes, with increasing cation size, is mainly caused by the decrease of the electrostatic and polarization stabilizations. 相似文献
20.
The formation constants of Li+, N+, K+, Mg2+ and Ca2+ phenoxyacetate complexes were determined potentiometrically using an (H+)-glass electrode at 10, 25, 37 and 45°C, at several ionic strengths, in the range 0.04?I? 0.9 mol 1?1. Simple empirical equations for the dependence of the formation constants on ionic strength were derived. From the temperature coefficients, estimates of ΔHo and ΔSo were obtained. 相似文献