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1.
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进样阀(I)     
高效液相色谱进样阀(或进样器)的作用是将一定量的样品送入色谱仪。样品在流动相的带动下进入色谱柱系统完成分离过程。现代高效液相色谱仪对于进样阀的要求如下:(1)耐高压,因为高效液相色谱通常要在35.0MPa或更高的压力下工作;(2)进样量精确;(3)进样重复性好;(4)方便、适用,且可根据需要选择不同的进样量;(5)价格低廉;(6)保证在色谱柱中心进样,操作时不产生流量或压力波动。到目前为止,液相色谱进样阀共有3种形式:1.手动注射进样器;2.手动进样阀;3.自动进样器。从原理上讲,自动进样器是在…  相似文献   

3.
The picolyl-substituted NHC complex [Au(im(CH(2)py)(2))(2)]PF(6) (1) reacts with two equivalents of copper(I) halides, affording compounds [Au(im(CH(2)py)(2))(2)(CuX)(2)]PF(6) (X = Cl, 2; Br, 3; I, 4). Each complex contains a nearly linearly coordinated [Au(NHC)(2)](+) center where the two picolyl groups on each im(CH(2)py)(2) ligand chelate a single copper atom. The Cu(I) center resides in a distorted tetrahedral environment and is coordinated to two pyridyl groups, a halide ion, and a gold metalloligand. The Au(I)-Cu(I) separations measure 2.7030(5), 2.6688(9), and 2.6786(10) ? for 2-4, respectively. Additionally, each Cu(I) center is further coordinated by a semibridging NHC ligand with short Cu-C separations of ~2.3 ?. In solution, these complexes dissociate the Cu(I) ion. In the solid state, 2-4 are photoluminescent with respective emission maxima of 512, 502, and 507 nm. The reaction of [Au(im(CH(2)py)(2))(2)]PF(6) with four equivalents of CuBr afforded the coordination polymer {[AuCu(2)Br(2)(im(CH(2)py)(2))(2)]Br·3CH(3)CN}(n) (5). This polymeric complex contains [Au(NHC)(2)](+) units interconnected by Cu(2)Br(2) dimers. In 5, the Au-Cu separations are long at 4.23 and 4.79 ?, while the Cu-Cu distance is considerably shorter at 2.9248(14) ?. In the solid state, 5 is photoluminescent with a broad band appearing at 533 nm.  相似文献   

4.
根据配合物H2C[P(Ph)2AUX]2(X=I,CI)和HC[P(Ph)2AUX]3(X=I,CI)的晶体结构对它们进行了从头算研究,在MP2近似水平下得到绕C-P旋转所产生构象的势能曲线,从而揭示AU(I)-AU(I)相互作用. 计算结果表明,在所研究的四个配合物中均存在AU(I)-AU(I)相互作用,该作用较弱,约为10. 0~16. 5kJ/mol,与Schmibaur的实验估计值和Pyykko等对其它模型配合物的计算结果接近.  相似文献   

5.
Polymeric compounds of the type (MCCR)x (MCu, Ag; R = cyclohexyl, n-hexyl) and M2(p-(CC)C6H4)] x (MCu, Ag) have been prepared. The preparation media and solvent (liquid ammonia, methanol and methanol/ or methanol-ether/aqueous ammonia) exert an influence over the nature of the alkynyl compound, leading either to the formation of adducts or to the formation of metal alkynylides with identical empirical formulae, but differing in colour, which seems be related to the different extent of molecular association.  相似文献   

6.
Auration of o-trimethylsilyl arylphosphines leads to the formation of gold and gold–silver clusters with ortho-metalated phosphines displaying 3c–2e Au−C−M bonds (M=Au/Ag). Hexagold clusters [Au6L4](X)2 are obtained by reaction of (L−TMS)AuCl with AgX, whereas reaction with AgX and Ag2O leads to gold–silver clusters [Au4Ag2L4](X)2. Oxo-trigold(I) species [Au3O]+ were identified as the intermediates in the formation of the silver-doped clusters. Other [Au5], [Au4Ag], and [Au12Ag4] clusters were also obtained. Clusters containing PAu−Au−AuP structural motif display good catalytic activity in the activation of alkynes under homogeneous conditions.  相似文献   

7.
合成了三维的超分子化合物(BPT)2(Ag2I6)(BPT为1,5-亚戊烷基二吡啶鎓阳离子),并对其进行了元素分析、红外光谱和X-射线单晶衍射测定.结构分析表明,该化合物属单斜晶系,空间群C2/c,晶胞参数a=2.569 14(2)nm,b=1.030 57(7)nm,c=1.682 67(1)nm,β=95.415 ...  相似文献   

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We have implemented a model of I 2 ? (CO2) n (2 ≤n ≤ 17) clusters and present an analysis of the minimum energy structures obtained from a quenching procedure. A discussion of the importance of various potential contributions to the energetics of the clusters is also presented. Given the current state of understanding of structural control of caging and the time scales of recombination and evaporation, this model has important implications for understanding the picosecond dynamics observed by the Lineberger group and for rigorous studies of evaporation rates.  相似文献   

10.
Two binuclear copper(I) complexes with novel structures and novel bonding,Cu_2(Ph_2PCH_2PPh_2)Cl_2 (Ph_2PCH_2PPh_2=dppm) and Cu_2(Ph_2P-CH_2CH_2PPh_2)Cl_2 (Ph_2PCH_2CH_2PPh_2=dppe), were prepared and characterized through elemental analyses, ICP, IR(4000-200 cm~(-1), CsI disc.), ~(31)P-NMR spectra. Their electronic conductivities, oxidation and reduction potentials were measured. Preliminary studies show that both of the two complexes have chlorobridging and phosphorus-bridging structures.  相似文献   

11.
Reactions of copper(I) halides with Se-donor ligands, namely, triphenylphosphine selenide (Ph3PSe) and bis(diphenylselenophosphinyl)methane (dppm-Se,Se) yielded bromo-bridged [Cu22-Br)2(SePPh3)2(NCCH3)2] (1), and selenium-bridged, [Cu2I23-dppm-Se,Se)2]?· 2CH3CN (2) dimers, whose crystal structures are described. Acetonitrile stabilizes 1 by coordinating and helps to stabilize the packing in crystals of 2.  相似文献   

12.
The properties of poly(3,4-ethylenedioxythiophene) (PEDT) film have been studied in iodide solutions by cyclic voltammetry and stripping voltammetry methods. It has been shown that formation of charge-transfer complexes between iodine species and polymeric rings promotes storage of iodine on an electrode covered by PEDT film. Due to this behaviour the PEDT layer can be employed for electroanalysis of dilute (10−4–10−3 M) solutions of iodide salts by stripping voltammetry methods. The possibility of PEDT film application for zinc-iodide rechargeable batteries was also examined.  相似文献   

13.
Rotationally resolved absorption spectra of I(2) (+) were recorded in 12 065-13 062 cm(-1) region by employing optical heterodyne velocity modulation absorption spectroscopy. In total, 4054 lines were assigned to 24 bands in the A(2)Π(3∕2,u)-X(2)Π(3∕2,g) system spanning the vibrational levels υ(') = 1-4 and υ(n) (') = 11-19. The assigned lines were globally fitted and an error of 0.003 cm(-1) was obtained. Rotational constants, B(υ), were used to derive equilibrium parameters B(e) (') = 0.03977725(77) cm(-1), a(e) (') = 1.1819(24)×10(-4) cm(-1), r(e) (') = 2.584386(25) A? of the X(2)Π(3∕2,g) state, and B(e) (') = 0.0305787(37) cm(-1), a(e) (') = 1.2353(23)×10(-4) cm(-1), r(e) (') = 2.94758(18) A? of the A(2)Π(3∕2,u) state. Vibrational energies were used to derive ω(e) (') = 239.0397(55) cm(-1), ω(e)x(e) (') = 0.64951(87) cm(-1) of the X(2)Π(3∕2,g) state and ω(e) (') = 138.103(11) cm(-1), ω(e)x(e) (') = 0.45027(34) cm(-1) of the A(2)Π(3∕2,u) state. The A(2)Π(3∕2,u) (υ(n) = 13) state was found to be rotationally perturbed by the a(4)Σ(1/2,u) (-) (υ(n) = 17) state through second-order spin-orbit coupling.  相似文献   

14.
本文综述了 CO2 选择性分离聚合物膜材料的研究现状。概括了气体在固体聚合物膜中以溶解 -扩散为机理CO2 的传质特点。 CO2 选择性分离聚合物膜材料可分为 4种 ,传统膜材料的物理或化学改性、聚合物共混、新聚合物膜材料的设计与合成及有机 -无机杂聚膜。论文最后提出了 CO2 选择性分离聚合物膜材料的研究方向。  相似文献   

15.
1 INTRODUCTION Metallosupramolecular species with metal-metal interactions have been designed and synthesized due to their potential applications as functional materi- als[1]. For Ag(I) coordination compounds, short Ag(I) –Ag(I) separations have been found in many bi- and polynuclear complexes[2~4], and these short metal- metal distances have been attributed to the ligand ar- chitecture[5, 6]. Thus, the rational design of bi- and polynuclear Ag(I) complexes must recognize the in- here…  相似文献   

16.
The title inclusion compound [{NH2(CH2CH2)2NCH2CH2NH2}2H][Cu4(CN)7] was obtained as single crystals from an aqueous solution containing CuCN, KCN, andN-(2-aminoethyl)piperazine. It crystallizes in the monoclinic space groupP2/n,a = 12.3829(9),b = 8.5970(9),c = 12.6633(7) Å, = 109.984(5)°,z = 2,R = 0.035 for 2921 independent reflections. The inclusion structure is composed of the hydrogen-bonded dimeric onium guest [{NH2(CH2CH2)2NCH2CH2NH2}2H]3+ and the negatively-charged three-dimensional host [CU4(CN)7]3– in which the CN-bridged framework Cu(I) atoms are all tetrahedral. A polyacene-like one-dimensional array of hexagons cornered by Cu(I) atoms and edged by -CN- linkages is arrayed in parallel to theb axis and stacked approximately along the c axis. The Cu(I) corner shared in the one-dimensional array extends an N-coordinate CN group along the c axis to a pair of unshared Cu(I) corners for which the C end behaves as a bifurcated ligand to build up the three-dimensional host structure. The cavity is composed of two networks of the hexagons at the top and bottom and pillared by six >CN- groups and accommodates a dimeric guest ofN-(2-aminoethyl)piperazinium cations protonated at each 4-N with the cations being hydrogen-bonded to each other through the 2-NH2 groups sharing another H+.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.  相似文献   

17.
Treatment of K(P3C2tBu2) with Cu2I2 and PMe3 gave the binuclear complex [Cu(PMe3)2(μ-P3C2tBu2)2Cu(PMe3)2] via the isolated intermediate compound [Cu(PMe3)2(μ-P3C2tBu2)(μ-I)Cu(PMe3)2]. The reaction of K(P3C2tBu2) with [AuCl(PEt3)] on the otherhand gave the cation:anion complex [Au(PEt3)2][Au(η1-P3C2tBu2)2]. All complexes were fully characterised by multinuclear spectroscopy and single crystal X-ray diffraction studies.  相似文献   

18.
Self-assembled 2 × 2 grids have been characterised as high-fidelity species produced when the correct stoichiometric ratios are met, but rarely are the individual steps leading to and from their formation characterised. Here, we present such a study using equilibrium-restricted factor analysis to model a set of UV–vis spectra starting from a bis-bidentate ligand to the assembly of a 2 × 2 grid complex upon titration with 1 equiv. of [Cu(MeCN)4](PF6) and to disassembly upon further titration. Intermediate species [CuL2]+, [Cu2L3]2+, [Cu3L2]3+ and [Cu2L]2+ are evidenced along the assembly and disassembly pathways. Complementary 1H NMR titrations are consistent with the rich set of complexes and equilibria involved. Given the nature of the assembly process, the assembly is entropy driven and likely enthalpy driven as well. The disassembly process is both enthalpy and entropy driven according to the standard free energy values derived from the modelling of the spectrophotometric titration data.  相似文献   

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20.
Treatment of [Pb(Stol)2]n with an equiv of [Et4N]Cl in DMF afforded a new 1-D polymeric complex, [(μ-Cl)Pb2(Stol)(μ-Stol)2]n (1), with Pb–Cl–Pb links. Interaction of 1 with a suspension of [Ag(Stol)] in DMF resulted in formation of a 2-D polymeric complex, [PbAg2(μ-Stol)24-Stol)2]n (2), with the planar four-membered Ag2S2 and PbAgS2 rings bridged by μ-Stol and μ4-Stol ligands. Both polymeric complexes were structurally characterized by single-crystal X-ray diffraction analysis.  相似文献   

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