首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 531 毫秒
1.
Two kinds of water-soluble metallophthalocyanines (Mt2Pc2), binuclear cobalt phthalocyanine (Co2Pc2) and binuclear ferric phthalocyanine (Fe2Pc2), were supported on silk fibers and modified viscose fibers to construct bioactive fibers of mimic enzyme, Mt2Pc2 used as the active center of bioactive fibers, viscose and silk fibers as the microenvironments. The catalytic oxidation ability of bioactive fibers on the malodors of methanthiol and hydrogen sulfide was investigated at room temperature. The experimental results demonstrated that the catalytic activity of such bioactive fibers was tightly correlative to the types of bioactive fibers and substrates.  相似文献   

2.
Two kinds of water-soluble metallophthalocyanines, binuclear cobalt phthalocyanine (Co2Pc2) and binuclear ferric phthalocyanine (Fe2Pc2), were synthesized through phenylanhydride-urea route and characterized by elemental analysis and FT-IR spectra. Binuclear metallophthalocyanine derivatives (Mt2Pc2) were immobilized on silk fibers and modified viscose fibers to construct bioactive fibers of mimic enzyme. Mt2Pc2 was used as the active center of bioactive fibers, viscose and silk fibers as the microenvironments. The catalytic oxidation ability of bioactive fibers on the malodors of methanthiol and hydrogen sulfide was investigated at room temperature. The experimental results indicated that the catalytic activity of such bioactive fibers was closely correlative to the types ofbioactive fibers and substrates.  相似文献   

3.
Mononuclear copper phthalocyanine (CuPc) and binuclear copper phthalocyanine (Cu2Pc2) were synthesized by the phenylanhydride-urea route, and their catalytic oxidation activity on 2-mercaptoethanol was studied. Based on the experimental results, a catalytic mechanism of Cu2Pc2 on 2-mercaptoethanol has been proposed. Furthermore, the effects of pH, Cu2Pc2 concentration, and temperature on the catalytic oxidation activity were evaluated. The results showed that CuPc has no catalytic activity, while Cu2Pc2 has high catalytic oxidation activity towards 2-mercaptoethanol with the optimal activity at pH 11. The reaction can further be enhanced by increasing Cu2Pc2 concentration and temperature, due to its endothermic characteristics.  相似文献   

4.
Cellulose was dissolved rapidly in a NaOH/thiourea aqueous solution (9.5:4.5 in wt.-%) to prepare a transparent cellulose solution, which was employed, for the first time, to spin a new class of regenerated cellulose fibers by wet spinning. The structure and mechanical properties of the resulting cellulose fibers were characterized, and compared with those of commercially available viscose rayon, cuprammonium rayon and Lyocell fibers. The results from wide angle X-ray diffraction and CP/MAS 13C NMR indicated that the novel cellulose fibers have a structure typical for a family II cellulose and possessed relatively high degrees of crystallinity. Scanning electron microscopy (SEM) and optical microscopy images revealed that the cross-section of the fibers is circular, similar to natural silk. The new fibers have higher molecular weights and better mechanical properties than those of viscose rayon. This low-cost technology is simple, different from the polluting viscose process. The dissolution and regeneration of the cellulose in the NaOH/thiourea aqueous solutions were a physical process and a sol-gel transition rather than a chemical reaction, leading to the smoothness and luster of the fibers. This work provides a potential application in the field of functional fiber manufacturing.  相似文献   

5.
为了确定双核金属酞菁化合物对亚硫酰氯还原反应是否具有比单核金属酞菁更强的电催化性能, 通过循环伏安测试方法, 用酞菁钴和酞菁铁作为对比, 研究了双核钴锰酞菁在1.5 mol·L-1 LiAlCl4/SOCl2电解液中的电催化行为, 并计算出动力学参数, 由此来评估具有平面结构的双核金属酞菁化合物对亚硫酰氯还原的催化活性的影响. 通过比较循环伏安曲线发现, 与单核酞菁钴(II)和酞菁铁(II)相比, 双核钴锰酞菁对SOCl2还原反应具有更好的催化活性, 能提高SOCl2还原反应的交换速率常数和SOCl2在玻碳电极上的扩散系数, 从而提高SOCl2还原电位和电流.通过ER14250型实体电池10 mA放电性能测试验证表明, 与单核酞菁钴和酞菁铁催化剂的电池相比, 双核钴锰酞菁在低温(-30 ℃)下可提高放电中点电压0.3 V, 在常温(25 ℃)下可以提高放电容量约100 mAh, 催化效果比单核酞菁钴和酞菁铁显著.  相似文献   

6.
We present the case of a nonchiral organogelator that forms hollow fibers and encapsulates silver nanoparticles (SNP) and a dye molecule. The biscarbamate molecule (a model compound for polyurethanes), which has two hydrogen-bonding motifs symmetrically attached to n-dodecyl side chains (C(12)), gels benzonitrile with hollow fibrillar morphology. The C(12) molecules form sheets that eventually wrap into hollow fibers to form the gel network. Herein, two-component gels were prepared with C(12) as one component and SNP, phthalocyanine (Pc), or perylene (Pe) as the other. Microscopic analysis and partial melting experiments confirmed the inclusion of the silver nanoparticles and phthalocyanine into the hollow fibers. On the other hand, Pe molecules tend to form crystals at the outer surface of the C(12) fibers, which results in a significant increase in the width of the gel fibers. This difference in the behavior of Pc and Pe molecules were accounted for by their crystal geometry and significantly different crystal growth rate compared with that of C(12) fiber formation in the gels. Pc crystallizes in a needle shape that facilitates occlusion in the gel fibers, whereas Pe forms large platelets. X-ray diffraction and spectroscopic analysis of the two-component gels along with their neat components confirmed that there was no change in the packing behavior of the Pc and Pe molecules in the gels. Therefore, these are examples of two-component physical gels in which the Pc crystals are occluded within the hollow fibers of C(12) by physical mixing of the components without the aid of any inter-molecular interactions between the different components. We have thus shown that lumen-loaded gel fibers with nanoparticles and dye molecules can be prepared by the two-component gel route, provided that the above growth rate, shape, and size conditions are satisfied.  相似文献   

7.
The soluble asymmetric phthalocyanine (Pc) (ZnPc-OH) was synthesized and used as a photosensitizer to degrade water pollutants. The catalytic ability of zinc Pc was proved by degrading Rhodamine B. In addition, ZnPc-OH, which has good solubility, can be used in photodynamic therapy.  相似文献   

8.
采用微波法合成了双核酞菁钴,并采用红外光谱、紫外可见光谱、热重分析对其进行表征。以二苯并噻吩(DBT)为反应底物,考察双核酞菁钴对DBT催化氧化性能,筛选出较优催化剂,并进行脱硫反应工艺条件优化。结果表明,双核酞菁钴具有较好的催化性能,在室温下、双核酞菁钴用量为0.01 g(cat)/5 m L、空气流量为80 m L/min、反应温度为40℃、反应1 h,DBT脱硫率达到97.17%。催化剂重复使用5次,催化效果无明显下降。氧化产物经红外光谱、质谱分析为DBTO2。对芳香烃及烯烃进行了催化氧化实验,发现该工艺对油品的质量基本无影响。  相似文献   

9.
We systematically investigated the weak epitaxy growth (WEG) behavior of a series of planar phthalocyanine compounds (MPc), i.e., metal-free phthalocyanine (H2Pc), nickel phthalocyanine (NiPc), copper phthalocyanine (CuPc), zinc phthalocyanine (ZnPc), iron phthalocyanine (FePc), cobalt phthalocyanine (CoPc), grown on a p-sexiphenyl ( p-6P) monolayer film by selected area electron diffraction (SAED) and atomic force microscopy (AFM). Two types of epitaxial relations, named as incommensurate epitaxy and commensurate epitaxy, were identified between phthalocyanine compounds and the substrate of the p-6P film. The tiny variation of the lattice constant of phthalocyanine compounds can result in different crystal orientations. The change rule of incommensurate and commensurate epitaxy was extracted. The tendency of commensurate epitaxy becomes weaker as the lattice constant b increases, while it gets stronger as the substrate temperature is elevated. Large size and continuous H2Pc films can be obtained by controlling the growth conditions. The WEG method is generally applicable in the whole family of planar phthalocyanine compounds and may be used to fabricate other high-quality organic films.  相似文献   

10.
The effects of alkyloxy substituents attached to one phthalocyanine ligand of three heteroleptic bis(phthalocyaninato) yttrium complexes Y(Pc)[Pc(α‐OCH3)4] ( 1 ), Y(Pc)[Pc(α‐OCH3)8] ( 2 ), and Y(Pc)[Pc(β‐OCH3)8] ( 3 ), as well as their reduction products {Y(Pc)[Pc(α‐OCH3)4]}? ( 4 ), {Y(Pc)[Pc(α‐OCH3)8]}? ( 5 ), and {Y(Pc)[Pc(β‐OCH3)8]}? ( 6 ) [H2Pc(α‐OCH3)4=1,8,15,22‐tetrakis(methyloxy)phthalocyanine; H2Pc(α‐OCH3)8=1,4,8,11,15,18,22,25‐octakis(methyloxy)phthalocyanine; H2Pc(β‐OCH3)8=2,3,9,10,16,17,23,24‐octakis(methyloxy)phthalocyanine] are studied by DFT calculations. Good consistency is found between the calculated results and experimental data for the electronic absorption, IR, and Raman spectra of 1 and 3 . Introduction of electron‐donating methyloxy groups on one phthalocyanine ring of the heteroleptic double‐deckers induces structural deformation in both phthalocyanine ligands, electron transfer between the two phthalocyanine rings, changes in orbital energy and composition, shift of electronic absorption bands, and different vibrational modes of the unsubstituted and substituted phthalocyanine ligands in the IR and Raman spectra in comparison with the unsubstituted homoleptic counterpart Y(Pc)2. The calculations reveal that incorporation of methyloxy substituents at the nonperipheral positions has greater influence on the structure and spectroscopic properties of bis(phthalocyaninato) yttrium double‐deckers than at the peripheral positions, which increases with increasing number of substituents. Nevertheless, the substituent effect of alkyloxy substituents at one phthalocyanine ligand of the double‐decker on the unsubstituted phthalocyanine ring and on the whole molecule and the importance of the position and number of alkyloxy substituents are discussed. In addition, the effect of reducing 1 – 3 to 4 – 6 on the structure and spectroscopic properties of the bis(phthalocyaninato) yttrium compounds is also discussed. This systemic DFT study is not only useful for understanding the structure and spectroscopic properties of bis(phthalocyaninato) rare earth metal complexes but also helpful in designing and preparing double‐deckers with tunable structure and properties.  相似文献   

11.
本文提出了通过接枝聚合物将丝素蛋白纤维的染色的设想:在染料分子上引入丙烯酰基,然后将其接枝到丝素蛋白纤维表面。将2-羟基-4-丙烯酰氧二苯酮(HAOBP),1-羟基-2-丙烯酰氧蒽醌(HAOAQ)和1,5,8-三羟基-2-丙烯酰氧蒽醌(THAOAQ)等三种染料,分别用无引发剂存在下的接枝聚合法接枝到丝素蛋白纤维表面,使丝素蛋白纤维分别染成了浅黄、浅红和浅紫三种颜色。这样染色了的丝素蛋白纤维在浓酸或浓碱溶液中回流,未发生任何裉色现象,并且其热稳定性和紫外稳定性也得到了显著的改善。力学性能未下降。采用甲基丙烯酸甲酯(MMA)与染料单体共同进行接枝聚合染色,可以提高丝素蛋白纤维的光泽度,并可将接枝整理和染色两道工序合而为一。HAOBP、HAOAQ和THAOAQ在丝素蛋白纤维上的接枝率(mol单体/g丝),具有如下顺序,HAOBP>HAOAQ<THAOAQ。该顺序与它们的亲水性顺序恰好相反,这一结果支持了Imoto等人的无引发剂存在下的接枝聚合发生在丝素蛋白纤维的疏水区域的观点。  相似文献   

12.
An ordered molecular assembly of heteroleptic bis(phthalocyaninato) rare earth complexes M(Pc)[Pc(OC8H17)8] [M = Tb, Lu; H2Pc = phthalocyanine; H2Pc(OC8H17)8 = 2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyanine] has been fabricated by the Langmuir-Blodgett (LB) technique and characterized by surface pressure-area isotherms, electronic absorption and polarized electronic absorption spectroscopy, low-angle X-ray diffraction, and atomic force microscopy. The molecular ordering in the LB multilayer film on SiO2 substrate was made into a p-channel field effect transistor (FET), which was generally operated in the enhanced mode. The energy levels of the highest occupied molecular orbital and the lowest unoccupied molecular orbital as well as the energy band diagram can be deduced from the electrochemical measurement results. The charge mobilities of Tb(Pc)[Pc(OC8H17)8] and Lu(Pc)[Pc(OC8H17)8] were calculated to be about 6.4 x 10(-4) and 1.7 x 10(-3) cm2 V(-1) s(-1), respectively.  相似文献   

13.
N-bridged diiron tetra-tert-butylphthalocyanine activates H(2)O(2) to form anionic hydroperoxo complex [(Pc)Fe(IV)=N-Fe(III)(Pc)-OOH](-) prone to heterolytic cleavage of O-O bond with the release of OH(-) and formation of neutral diiron oxo phthalocyanine cation radical complex, PcFe(IV)=N-Fe(IV)(Pc(+)˙)=O. ESI-MS data showed stability of the Fe-N-Fe binuclear structure upon formation of this species, capable of oxidizing methane and benzene via O-atom transfer. The slow formation kinetics and the high reactivity preclude direct detection of this oxo complex by low temperature UV-vis spectroscopy. However, strong oxidizing properties and the results of EPR study support the formation of PcFe(IV)=N-Fe(IV)(Pc(+)˙)=O. Addition of H(2)O(2) at -80 °C led to the disappearance of iron EPR signal and to the appearance of the narrow signal at g = 2.001 consistent with the transient formation of PcFe(IV)=N-Fe(IV)(Pc(+)˙)=O. In the course of this study, another high valent diiron species was prepared in the solid state with 70% yield. The M?ssbauer spectrum shows two quadrupole doublets with δ(1) = -0.14 mm s(-1), ΔE(Q1) = 1.57 mm s(-1) and δ(2) = -0.10 mm s(-1), ΔE(Q2) = 2.03 mm s(-1), respectively. The negative δ values are consistent with formation of Fe(iv) states. Fe K-edge EXAFS spectroscopy reveals conservation of the diiron Fe-N-Fe core. In XANES, an intense 1s → 3d pre-edge feature at 7114.4 eV suggests formation of Fe(iv) species and attaching of one oxygen atom per two Fe atoms at the 1.90 ? distance. On the basis of M?ssbauer, EPR, EXAFS and XANES data this species was tentatively assigned as (Pc)Fe(IV)=N-Fe(IV)(Pc)-OH which could be formed from PcFe(IV)=N-Fe(IV)(Pc(+)˙)=O by hydrogen atom abstraction from a solvent molecule. Thus, despite unfavourable kinetics, we succeeded in the preparation of the first dirion(iv) phthalocyanine complex with oxygen ligand, generated in the (Pc)Fe(IV)=N-Fe(III)(Pc) - H(2)O(2) system capable of oxidizing methane.  相似文献   

14.
基于在生理、催化等方面研究中的重要作用,H_2Pc分子的电子结构一直受到广泛的注意和研究。但是,理论上算出的电荷分布与实验上测出的NIS XPS信息,目前还不相符。为此,本文用CNDO/2计算方法,对应H_2Pc的文献几何构型,进一步考察了H_2Pc与H_2Pc'的电子结构。计算方法和结果H_2Pc和H_2Pc'的骨架构型见图1。对于固态与气态的H_2Pc,目前多数人认为其具有D_(2h)点群对称性(尽管作为D_(4h)点群对称性的根据也是存在的)。为考察分子构型改变(特别是切割)对分子的电子结构、特别是电荷分布的影响,我们  相似文献   

15.
Comparative investigations of adsorption properties of chlorhexidine (CHX) on two cellulose fibers, bleached cotton and viscose, were studied in order to obtain dry gauzes covered with known amount of this antiseptic. Adsorption isotherm results carried out at 293 and 323 K can be described by Langmuir isotherm model, nevertheless, at high concentration correlation is better to Freundlich isotherm. Electrokinetic potential evolution with CHX concentration, shows that initial negative zeta potential of cotton and viscose diminish its absolute value as the concentration of the treatment increases; both fibers present an isoelectric point at high concentration of CHX that is 0.3 mM for viscose and 0.8 mM for cotton. Electrostatic interactions between cationic groups of CHX and carboxylic acid groups of the fibers could explain adsorption at low concentration, but when it is higher than these values, possible hydrogen bonding between the amine groups of CHX and hydroxyl groups of cellulose could explain increasing adsorption when it is hindered by electrostatic repulsion as it is predicted by Freundlich model, that describes heterogeneous surface and multilayer adsorption. Adsorption kinetics isotherms reveal that the process is quick with t 1/2 values of 5.4 min for cotton and 2.8 min for viscose. Differences in adsorption behaviour between the two fibers could be attributed to structural differences as we have observed from estimation of CI index based on FTIR spectra. Values obtained 1.6 for viscose and 2.2 for cotton could explain that the amount of CHX adsorbed on viscose is higher than it is on cotton. Finally desorption experiments performed with 0.01 M of NaCl solution at room temperature and pH 6 reveals the possibility of therapeutical application of these fibers although further investigations must be done to optimize the process.  相似文献   

16.
We present here X-ray specular reflectivity (XRR) characterization of the ordering of Langmuir-Blodgett films of the liquid crystalline phthalocyanine (Pc) 2,3,9,10,16,17,23,34-octakis(2-benzyloxyethoxy)copper(II) phthalocyanine, 1, on Si(100) wafers with a native oxide layer and these same substrates modified with monolayers of varying percentages of methyl- and phenyl-terminated silanes. The central copper atom in these Pc's provides for high contrast in X-ray reflectivity for single-bilayer films of 1. The XRR data are modeled as arising from multiple layers of organic material, above and below the rows of copper atoms in the aligned Pc cores; variations in the total thickness of these films, and the spacing between the rows of copper atoms, are attributed to changes in the interaction with the substrate, and changes in the Pc orientation and side chain packing. The most pronounced effect on these parameters comes from variations in the ratio of the phenyl-silane versus methyl-silane content of the substrate modifiers and annealing of these films past their crystalline (K) --> liquid crystalline (LC) mesophase transition temperature. Transfer of multiple bilayers of this Pc leads to additional changes in the thickness of each layer, eventually forming a hexagonal close-packed array, reminiscent of bulk fibers of this material, as revealed by X-ray diffraction (XRD).  相似文献   

17.
The phase behaviour of metal-free phthalocyanine (H2Pc) has been studied in a differential scanning calorimeter. The effect of the thermal history of samples on the DSC curves was investigated to obtain data concerning the phase transition which appeared on α as well as β forms of H2Pc over the termperature range from 250 to 340 K. To characterize the α metal-free phthalocyanine at low temperatures, the capacitance of an Ag(H2Pc)Al sandwich was measured as a function of the temperature. The specific heats of the α and β forms of H2Pc and the heat of the α → β polymorphic transition were measured. Kinetic parameters of the α → β polymorphic transition have been derived from the calorimetric results.  相似文献   

18.
The catalytic activity of a binuclear complex of a macroheterocyclic compound (MHCC) containing cobalt(II) and having an enlarged coordination cavity is studied by cyclic voltammetry. Basic features of the electrochemical behavior of MHCC Co2O2 in alkaline solution are found. The complex has a higher catalytic activity as compared to cobalt phthalocyanine.  相似文献   

19.
The present paper reports uniqueness of a simple, programmed design of disk-shaped homochiral nickel phthalocyanine (Pc) molecules bearing four enantiomerically pure 1-(p-tolyl)ethylaminocarbonyl groups at their peripheral positions, (Pc-(R) and Pc-(S)), and their controlled self-organization into mesoscopic supramolecular helical fibers with a preferential handedness in solution and onto solid surfaces. A combination of four fundamental intermolecular interactions, including quadruple hydrogen bonding, pi-pi stacking, homochiral interactions of the enantiopure bulky aralkyl entities, and noncoordinating nature of nickel ion of the Pc molecules afforded a high thermal stability of the Pc self-assembly in chloroform (CHCl(3)), tetrahydrofuran, and o-dichlorobenzene and onto hydrophilic mica and hydrophobic HOPG surfaces. A higher-ordered helical self-assembly of Pc disks was observed in these solutions (approximately 200 Pc molecules), while the self-assembly was completely dissociated into monomeric species in N,N-dimethylformamide due to a loss of hydrogen-bonding interactions between Pc molecules. Supramolecular chirality in the hierarchical self-assembly of Pc molecules originated from the presence of (R)- or (S)-chiral centers in the peripheral tails, which rotate noncovalently linked molecular building blocks to effectively form the helical architectures. The helical Pc nanofibers dissolved in CHCl(3), estimated to be ca. 70 nm from peak molecular weight obtained by SEC analysis, acts as a building block for higher-order helical fibers (ca. 1 microm) at single molecular level on the solid surfaces, as demonstrated by the dynamic force mode atomic force microscopy. Regardless of hydrophilic and hydrophobic substrates, the interaction between these Pc molecules and the solid surfaces could not affect the morphology of helical assemblies, indicating a unique robustness of these assemblies.  相似文献   

20.
Natural silk as a biodegradable, biocompatible, renewable, green and abundant biomaterial was used as a support for chemical immobilization of a water‐soluble manganese(II) complex with a phthalocyanine ligand possessing covalent binding ability. The prepared manganese(II) tetrasulfophthalocyanine complex supported on natural silk revealed efficient catalytic activity and reusability for the synthesis of benzoxazepine derivatives in water at room temperature.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号