8-HQ插层铝合金MAO-LDHs复合膜的自修复行为研究

为进一步提高铝合金微弧氧化(MAO)膜的抗腐蚀能力,通过三步处理获得了MAO-LDHs/8-HQ复合膜,即制备基础MAO膜、负载铝镁水滑石(LDHs)和插层8羟基喹啉(8-HQ)。对三种膜的形貌与物相进行分析,并将三种膜破损后浸入3.5%(质量分数)NaCl水溶液中48 h,利用电化学工作站、SEM、EDS等设备与手段着重探讨了复合膜的抗腐蚀自修复行为。形貌表征与物相分析结果显示,基础MAO膜呈典型疏松多孔状;经水热合成后,铝镁LDHs呈片状结构负载在基础膜表面,将微孔完全封闭;插层处理后,HQ-进入LDHs层间,其SEM形貌无明显改变。电化学测试结果显示,MAO-LDHs/8-HQ复合膜、MAO-LDHs复合膜和MAO膜的自腐蚀电流密度分别为5.877×10^(-7)、2.262×10^(-6)和7.832×10^(-6)A/cm^(2),前者明显小于后两者;自腐蚀电位分别为-0.633、-0.611、-0.613 V,三者基本一致,这说明8-HQ的存在可以显著抑制MAO膜的腐蚀行为。经48 h盐浴腐蚀后,MAO-LDHs/8-HQ复合膜划痕处出现了富含HQ-特征元素(N)的花瓣状沉积物,该沉淀物附着在基体上。上述结果推测,破损后的复合膜在腐蚀环境下释放出HQ-并与基体中的Al 3+发生螯合反应形成沉积物,进而实现膜层的自修复。

Thickness Dependent Behavior of Photoluminescence of Tris(8-hydroxyquinoline)Aluminum Film

In situ thickness dependent photoluminescence （PL） measurements of tris（8-hydroxyquinoline） aluminum（Alq3） film were performed. At the beginning of Alq3 deposition on the glass substrate, the Alq3 emission showed a sharp red-shift. Further deposition of Alq3 resulted slight red-shift, and finally tended to saturated value. The total red-shift of about 12 nm was observed for the Alq3 film thickness range from 2 to 500 nm.This red-shift was attributed to the change from the 2D to 3D exciton state with increasing Alq3 film thickness. Meanwhile, the PL intensity of Alq3 emission increased continuously, and showed a rate change at the initial deposition of Alq3 due to non-rediative decay of excitons arised from the interaction between excitons and the substrate, and finally tended to saturation with the Alq3 thickness.

Thermochemical Study on Coordination Complex of Samarium with Salicylic Acid and 8-Hydroxyquinoline

The coordination complex Sm（C7H5O2）2·（C9H6NO）, synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline, was characterized with IR, elemental analysis, molar conductance, and thermogravimatric analysis. The standard molar enthalpies of solution of [ SmCl3·6H2O （s） ], [ 2C7H6O3 （s） ], [ C9H7NO （ s ） ] and [ Sm （C7H5O3） 2·（ C9H6NO ） （ s ） ] in the calorimetric solvent were determined with the solution-reaction isoperibol calorimeter at 298.15 K to be △sHm^- [ SmCl3·6H2O （s）, 298.15 K ] = - 103.98 ± 0.04 kJ·mol^-1, △sHm^- [2 C7H6O3 （s）, 298.15 K] = 16.35±0.14 kJ·mol^-1,△sHm^-[C9H7NO （s）, 298.15 K] = -6.11±0.08 kJ·mol^-1 and △sHm^-[Sm（C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 130.08 ± 0.04 kJ·mol^-1, respectively. The enthalpy was determined to be △rHm^- = 89.59 ±0.18 kJ·mol^-1 for the reaction SmCl3·6H2O（s） ＋ 2C7H6O3（s） ＋ C9H7NO（s） = Sm （C7H5O3） 2·（C9H6NO） （ s ） ＋ 3HCl （g） ＋ 6H2O （ l ）. According to the above results and the data given in literature and through Hess＇ law, the standard molar enthalpy of formation of Sin（ C7H5O3 ）2·（C9H7NO）（s） was estimated to be △rHm^- [ Sm （C7H5O3）2·（C9H6NO） （s）, 298.15 K] = - 2055.9 ± 3.03 kJ·mol^-1.

Crystal Structure and Characterization of a Binuclear Cd(Ⅱ) Quaternary Coordination Complex [Cd_2(phen)_2Q_2(BP)]_n(phen=1,10-Phenanthroline,BP = Biphenyl-4,4'-dicarboxylic acid,Q=8-Hydroxyquinoline Anion)

The structure of a binuclear cadmium（Ⅱ） quaternary complex, [Cd2（phen）2- Q2（BP）]n 1 （phen = 1,10-phenanthroline, BP = biphenyl-4,4′-dicarboxylic acid, Q = 8-hydroxy- quinoline-anion）, has been determined by X-ray crystallography and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. It crystallizes in the monoclinic system, space group P21/n with a = 13.1906（18）, b = 10.9623（15）, c = 16.947（2）A, β = 111.3430（10）°, V = 2282.5（5）A^3, Z = 4, Mr = 556.85, Dc = 1.620 g/cm^3, F（000） = 1116,μ= 0.994 mm^-1 and S = 1.056. In the structure, 1D chains are connected via biphenyl-4,4′-dicarboxylic acid, 8-hydroxy quinoline anion and binuclear cadmium atoms into an infinite 1-D molecular chain architecture. Via aryl ring π-π stacking interactions a supramolecular structure is formed in 1.

Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline

The synergistic extraction of Pr^3＋ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester （P507, HL） and 8-Hydroxyquinoline （HQ） in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr^3＋ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration oil extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr^3＋.

Bipolar resistive switching based on bis(8-hydroxyquinoline) cadmium complex:Mechanism and non-volatile memory application

Stable and persistent bipolar resistive switching was observed in an organic diode with the structure of indium-tin oxide （ITO）/bis（8-hydroxyquinoline） cadmium （Cdq2）/Al. Aggregate formation and electric field driven trapping and detrapping of charge carriers in the aggregate states that lie in the energy gap of the highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO） of the organic molecule were proposed as the mechanism of the observed bipolar resistive switching, and this was solidly supported by the results of AFM investigations. Repeatedly set, read, and reset measurements demonstrated that the device is potentially applicable in non-volatile memories.

A Hydrogen Bond Stabilized 3D Network Built from Pyrazine-2,3,5,6-tetracarboxylic Acid and 8-Hydroxyquinoline

8-Hydroxyquinoline salt of pyrazine-2,3,5,6-tetracarboxylic acid [HQ]2[H2pztc]· 2H2O （1） was prepared and characterized by single-crystal X-ray diffraction, NMR, IR, TGA, elemental analysis and fluorescent measurements. Compound 1 crystallizes in orthorhombic, space group Pbcn with a = 9.953（3）, b = 15.966（3）, c = 16.081（5） A, V = 2555.5（13） A3, Z = 4, μ = 0.122 mm^-1, Dc = 1.514 Mg/m3, T= 296（2） K, C26H22N4O12, Mr = 582.48, F（000） = 1208, S = 1.006, R = 0.0448 and wR = 0.1149. Compound 1 has a three-dimensional （3D） network, in which pyra- zine-2,3,5,6-tetracarboxylic acids build up two-dimensional （2D） sheets and 8-hydroxyquinoline cations and water molecules act as pillars to connect the 2D sheets into an extended 3D network through strong intermolecular hydrogen bonding and π…π stacking interactions. Especially, a very short O-H…O hydrogen bond （O…O 2.470（2） A） between two neighboring [H2pztc] anions was observed.

Theoretical Studies on the Ground State and Excited State of 2,7′- （Ethylene）-bis-8-hydroxyquinoline

2,7′-（Ethylene）-bis-8-hydroxyquinoline was optimized with DFT/B3LYP and ab initio HF methods, so ion- ization potential and electron affinity could be determined. Absorption spectrum was calculated by ZINDO and TD-DFT. CIS method was used to calculate the S1 excited states of the compound and afterwards the emission spectrum was computed. When the solvent effect was taken into account, the computed results show encouraging agreement with known experimental data. The results of analyzing the relationship between the energies and absorption spectra indicate that the ability to transporting electrons is strengthened compared with 8-hydroxyquinoline and that absorption and emission spectra are red-shifted. The intramoleeular reor- ganization energy of tris（2,7′-（ethylene）-bis-8-hydroxyquinoline）-aluminum implies its electron transporting property is worse than tris（8-hydroxyquinoline）-aluminum. The predicted maximum emission wavelength is red-shifted compared with tris（8-hydroxyquinoline）-aluminum.

Synthesis and Structural Characterization of [Co(Q)_2(H_2O)_2](Q=8-Hydroxyquinoline Ion)

The single crystal of bi（8-hydroxyquinoline） bihydrated cobalt （Ⅱ） complex, [ Co（Q）2 （H2O2 ] （Q = 8-hydroxyquinoline ion）, has been synthesized by general method and structurally characterized by single crystal X-ray diffraction. Crystal data： C18H16CoN2O4, monoclinic, C2/c, α = 1.336 2（4） nm, b = 0.941 2（3） nm, c = 1.354 3（4） nm, β= 109.672（4）°, Z = 4. In the complex, Co（ Ⅱ ） ion is six-coordinated, forming a distorted octahedron. H-bonding and π-π stacking interaction play a significant role to form and stabilize the three-dimensional structure.

ABSORPTION SPECTRA OF 4f ELECTRON TRANSITIONS OF NEODYMIUM COMPLEX WITH 8-HYDROXYQUINOLINE AND OCTYLPHENOL POLY(ETHYLENEGLYCOL)ETHER

In this paper the absorption spectra of 4f electron transitions of the neodymlum complex with 8-hydroxyquinoline and octylphenol poly(ethyleneglycol)ether have been studied. The marked intensification of the band at low octylphenol poly(ethyleneglycol)ether concentration is found normally at 575 nm, and its resolution into three sharp bands centering at 572, 580 and 584 nm. The absorbances of the absorption maxima are 3.5 (at 572 nm), 7.2 (at 580 nm) and 10.2 (at 584 nm) times greater than that of the chloride.

Metal Complexes with 8-Hydroxyquinoline: Synthesis and <i>In Vitro</i>Antimicrobial Activity

In this paper, three complexes with 8-hydroxyquinoline (8-HQ) were synthesized, their spectral analysis was performed and the antimicrobial effect was examined in vitro. The stoichiometric ratio of the complex was determined conductometrically and spectrophotometrically. FTIR and UV/VIS spectroscopy were used for structural characterization. Antimicrobial activity was examined by diffusion technique on selected gram-positive and gram-negative bacteria, and C. albicans. Square planar and octahedral geometry complexes were synthesized by mixing in a molar ratio of 1:2 (M:L). Based on the spectral data, it is concluded that both oxygen and nitrogen atoms from 8-HQ are involved in the formation of the complex. The antimicrobial activity of the complexes is high, with zones of inhibition in the range of 15 - 28 mm. 8-HQ was shown to have a significantly higher ability to inhibit the growth of the tested microorganisms.

8-HQ瓶插液保鲜绣球花效应的研究

采用不同浓度的8-HQ作为瓶插液对绣球花进行保鲜研究。以绣球花(夏延品种)为材料,共设6组保鲜处理,当插花萎蔫时测定各处理组的瓶插保鲜期、鲜重;观察表皮细胞的显微结构。从瓶插寿命期、鲜重及表皮细胞的显微结构分析,在浓度500mg/L的8-HQ瓶插液处理下,绣球花瓶插保鲜期达7.5d,超过对照组3.5d;表皮细胞形态完整,胞间连丝保持连续、贯穿。500mg/L的8-HQ瓶插液对绣球花保鲜的效果,以及对表皮细胞的形态和胞间连丝的维持效果最好。

Preparation and Characterization of Carboxyl Functionalized Fluorescent Mesoporous Silica Nanoparticles Containing 8-Hydroxyquinolinate Zinc Complexes

Fluorescent mesoporous silica nanoparticles functionalized with carboxyl group(Znq-CMSCOOH) were successfully synthesized by in situ formation route of 8-hydroxyquinolinate zinc complexes in channels of mesoporous silica nanoparticles and post-grafting of carboxyl group on the surface. Moreover,the particle size and structural properties of Znq-CMS-COOH were characterized by transmission electron microscopy(TEM),field emission scanning electron microscopy(FE-SEM),dynamic light scattering(DLS),Fourier transform infrared spectroscopy(FT-IR),UV-vis spectrometer, fluorescence spectrometer and nitrogen adsorption-desorption measurements. The obtained results suggest that the Znq-CMS-COOH presents the uniform spherical shape with the mean diameter of about 85 nm and the obvious wormhole arrangement mesoporous. In addition, the Znq-CMS-COOH possesses green fluorescence with the emission peaks at 495 nm. So the Znq-CMS-COOH, which is beneficial to further modification and tracing, might be a great potential carrier for applying in drug delivery system in the future.

Synthesis and Crystal Structure of a Cr(Ⅲ) Dimer[Cr_2(8-hqn)_2Cl_4(H_2O)_2]·2(CH_3)_2CO (8-hqn=8-Hydroxyoxyquinolate)

The title complex [Cr2（8-hqn）2Cl4（H2O）2]·2（CH3）2CO （8-hqn = 8-hydroxyoxyquinolate） has been synthesized and characterized by single-crystal X-ray diffraction. It crystallizes in the triclinic system, space group P^-1 with a = 8.719（1）, b = 9.226（1）, c = 9.717（1） A^°, α = 71.916（2）, β= 78.072（2）, γ = 76.014（2）°, V= 713.72（15） A^°^3, Z= 1, Dc= 1.597g/cm^3, F（000） = 350 and μ（MoKa） = 1.177 mm^-1, the final R = 0.0490 and wR = 0.1055 for 1616 observed reflections with I 〉 2σ（I）. It is a dimer constructed by two monomeric units [Cr（8-hqn）Cl2（H2O）] bridged by phenoxide-like oxygen atom from 8-hydroxyoxyquinolate, where the two six-coordinated Cr（Ⅲ）atoms exhibit an octahedral coordination geometry.

铝-8-羟基喹啉配合物静态结构和动态水交换的密度泛函理论研究

采用密度泛函理论(DFT)量子化学计算方法对铝-8-羟基喹啉配合物(Al-8-Hq)的静态结构以及水交换反应进行了研究,系统地开展了以下工作:(1)采用GP-PCM(气相模型并考虑本体溶剂效应)在B3LYP6-311+G(d,p)水平优化了Al-8-Hq溶液中可能存在的8种构型,获得了相应的静态结构参数、NPA电荷和能量;(2)采用GIAO方法在HF 6-311+G(d,p)水平下计算了1∶3配合物的27Al NMR化学位移,结果表明采用HF的GP-PCM模型化学位移计算值与实验值一致;(3)通过模拟1∶1/1∶2配合物8个不同位点的动态水交换反应,探讨了水交换反应机制并预测了水交换反应速率.本研究有助于从原子层面加深对Al-8-Hq配合物形态结构以及水交换反应动力学过程的理解和认识.

Efficient Synthesis of 2-(8-Quinolinoxy)-4H-imidazolin-4-ones

The title compounds 2-(8-quinolinoxy)-4 H -imidazolin-4-ones(4) were synthesized by means of base catalytic reactions of 8-hydroxyquinoline with each of carbodiimides 2, which were obtained via aza-Wittig reactions of iminophosphoranes 1 with the corresponding aromatic isocyanates.

Conjugated 8-Hydroxylquinoline-Based Fluorescent Chemosensor for Zn^(2+) and Cd^(2+) and Bioimaging Application in Living Cells

A conjugated 8-hydroxyquinoline( 8-HQ)-based fluorescent chemosensor( 1) for Zinc ion( Zn^(2+)) and Cadmium ion( Cd^(2+)) was developed in aqueous solution and used for Zinc ion living cells bioimaging. The probe 1 was weakly fluorescent,but displayed a strong fluorescence at 580 nm with a large Stokes shift of150 nm in the presence of Zn^(2+) or Cd^(2+). This probe allows the detections of Zn^(2+) in the range of 0. 8-10 μmol/L and Cd^(2+) in the range of 0. 8-8 μmol/L,with the limit of detections of 0. 2 and 0. 6μmol/L for Zn^(2+) and Cd^(2+),respectively. The present probe was successfully used for fluorescence bioimaging of Zn^(2+) or Cd^(2+) in the living cells.

Mitigating phytotoxicity of tetracycline by metal-free 8-hydroxyquinoline functionalized carbon nitride photocatalyst

Photooxidative removal of pharmaceuticals and organic dyes is an effective way to eliminate growing micropollutants. However, photooxidation often results in byproducts as secondary hazardous substances such as phytotoxins. Herein, we found that photooxidation of common antibiotic tetracycline hydrochloride(TCH) over a metal-free 8-hydroxyquinoline(8-HQ) functionalized carbon nitride(CN) photocatalyst significantly reduces the TCH phytotoxic effect. The phytotoxicity test of photocatalytic treated TCH-solution evaluated towards seed growth of Cicer arietinum plant model endowed natural root and shoot growth.This study highlights the conceptual insights in designing of metal-free photocatalyst for environmental remediation.

Ethylene Oligomerization to Low Carbon Olefins by a Zirconium Complex Incorporating 8-Quinolinolato Ligands at a Low Al/Zr Ratio

Bis(8-quinolinolato)zirconium dichloride (Ox)2ZrCl2 (Ox- = 8-quinolinolato) was found active for ethylene oligomerization with a high selectivity of 84~94% to C4~C10 olefins at 70~100C under the pressure of 1.8 MPa using Et2AlCl as a co-catalyst (Al/Zr = 60).

Evaluating the Efficiency of Cadmium Removal by Alginate Hydrogels from Water Using 5,7-Dibromo-8-hydroxyquinoline as a Complexing Reagent

Cadmium toxicity in wastewater is a rising concern due to industries like batteries,metallurgy,electroplating,plastic stabilizers,and pigments.The quantitative detection of Cd^(2+)and its remediation from wastewater samples are of major concern from an environmental point of view.In the present work,an effective spectrophotometric method has been reported using 5,7-dibromo-8-hydroxyquinoline(DBHQ)as a complexing agent for Cd^(2+).This method has advantages like using recyclable,less toxic solvents and easy sample preparation.The limit of detection,limit of quantification,and sensitivity of the proposed method were found to be 33.30,36.70 mg L^(−1),and 2×10^(−3),respectively.The DBHQ method was validated using atomic absorption spectroscopy,and the recovery percentage was more than 98%.These results indicate that DBHQ can be effectively used for monitoring Cd^(2+)in aqueous systems.The method developed was further employed for monitoring Cd^(2+)adsorption on calcium alginate(AL)hydrogels.Batch adsorption studies were done to optimize parameters of Cd^(2+)removal using AL hydrogels,and the data obtained were used for kinetic and thermodynamic studies.Kinetic studies indicated that the pseudo-first-order model showed better fitting,and thermodynamic studies showed Freundlich-like adsorption.The maximum adsorption capacity of Cd^(2+)on AL hydrogels was found to be 56.45 mg g^(−1).The validation studies of DBHQ were performed using statistical analysis methods like t-tests and one-way variance.