寡甘醇单烷基醚的合成和性能

以寡甘醇和卤代烷为原料,利用相转移催化Ｗｉｌｌｉａｍｓｏｎ法合成了１２种寡甘醇单烷基醚,均获得较高产率。讨论了寡甘醇单醚合成的反应历程,并对其物理常数、水溶液的表面张力、起泡性能、临界胶束浓度进行了测试和分析。     

Synthesis and characterization of cellulose ethers/Eu(III)

The coordination complexes of the crystalline structure of cellulose ethers/Eu(III) with fluorescence emission, viz CMC/Eu(III), MC/Eu(III), and HEC/Eu(III), were synthesized and characterized. Results showed the emission spectra of Eu³⁺ ions in these coordination compounds, which originates from electric dipole transition. The main emission peak at 615 nm generated from ⁵D₀→⁷F₂ transition of Eu³⁺ ions. Their absorption and excitation spectra were different, because the effect of the high polarity of water and having both hydrogen bond donor and acceptor properties on the excited molecule is different from the effect on the ground state of the molecule. Our study demonstrated that the Degree of Substitute (DS) of CMC could influence the fluorescence intensity (FI) of CMC/Eu(III). The emission intensity of CMC/Eu(III) varies with the DS of CMC. For example, when the DS of CMC was 0.89, the FS (fluorescent spectra) of solid CMC/Eu(III) displayed three emission peaks Eu(III): the strongest emission peak at 615 nm (⁵D₀→⁷F₂ transition) and other two weaker peaks at 583 nm (⁵D₀→⁷F₁ transition) and at 652 nm (⁵D₀→⁷F₃ transition), respectively. The concentration of Eu(III) could also affect the FI of these coordination complexes. The FI of the coordination complexes peaked at 615 nm all reached maximum when Eu³⁺ concentration was at 5% (wt/wt). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 743–747, 2005     

Synthesis and adsorption properties for metal ions of crosslinked chitosan acetate crown ethers

Two novel chitosan derivatives—crosslinked chitosan dibenzo‐16‐c‐5 acetate crown ether (CCTS‐1) and crosslinked chitosan 3,5‐di‐tert‐butyl dibenzo‐14‐c‐4 diacetate crown ether (CCTS‐2)—were synthesized by the reaction of crosslinked chitosan with dibenzo‐16‐c‐5 chloracetate crown ether and 3,5‐di‐tert‐butyl dibenzo‐14‐c‐4 dichloracetate crown ether with the intent of forming polymers that could be used in hazardous waste remediation as toxic metal‐binding agents in aqueous environments. Their structures were confirmed with elemental analysis, infrared spectral analysis, and X‐ray diffraction analysis. In the infrared spectra of CCTS‐1 and CCTS‐2, the characteristic peaks of aromatic backbone vibration appeared at 1595 cm⁻¹ and 1500 cm⁻¹; the intensity of the N H and O H stretching vibration in the region of 3150–3200 cm⁻¹ decreased greatly. The X‐ray diffraction analysis showed that the peak at 2θ = 20° decreased greatly in CCTS‐1 and CCTS‐2. The adsorption and selectivity properties of CCTS‐1 and CCTS‐2 for Pb²⁺, Cu²⁺, Cr³⁺, and Ni²⁺ were studied. Experimental results showed that the two crosslinked chitosan derivatives had not only good adsorption capacities for Pb²⁺, Cu²⁺, but also high selectivity for Pb²⁺, Cu²⁺ in the coexistence of Ni²⁺. For aqueous systems containing Pb²⁺, Ni²⁺, or Cu²⁺, Ni²⁺, CCTS‐1 only adsorbed Pb²⁺ or Cu²⁺. For aqueous systems containing Pb²⁺, Cr²⁺ and Ni²⁺, CCTS‐2 had high adsorption and selectivity properties for Pb²⁺. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2069–2074, 1999     

Inhibition and polarization studies of some substituted urea compounds for corrosion of aluminium in nitric acid

Inhibition and polarization properties of urea, thiourea (TU), acetyl thiourea (AcTu), phenyl thiourea (PhTu), o-tolyl thiourea (o-tol Tu), m-tolyl thiourea (m-tol Tu), p-tolyl thiourea (p-tol Tu), 1:3-diphenyl thiourea (di-phTu), 1:3-di-o-tolyl thiourea (di-o tol Tu), 1:3-di-m-tolyl thiourea (di-m-tol Tu) and 1 : 3-di-p-tolyl thiourea (di-p-tol Tu) have been studied in relation to the corrosion of aluminium (1060) in 20% nitric acid. The polarization experiments were carried out using potentiostatic method. The inhibition efficiencies of the inhibitors were determined at 25°, 35° and 45°C and it has been observed that the percentage inhibition efficiencies of the inhibitors increase with increase in temperature. All the inhibitors except urea obey the Langmuir adsorption isotherm below the inhibitor concentration of 300 ppm, but in no case are slopes equal to unity observed. At and above the concentration of 300 ppm, the effectiveness of the compounds decreases, which is attributed to their action as cathodic depolarizers. The inhibitive performance of the compounds is discussed in the light of electronic effects in the thioureas. The potentiostatic anodic polarization curves in the presence of the inhibitors shift towards lower current density region as compared with the curve of the uninhibited solution, but there is no proper correlation between the inhibition efficiencies and the current densities required for the passivation of aluminium.     

Characterization,in vitro bioactivity and biological studies of sol-gel synthesized SrO substituted 58S bioactive glass

Bioactive glasses (BGs) are considered as a high potential candidate in bone repair and replacement. In the present study, sol–gel derived BGs based on 60% SiO₂-(36%-x) CaO-4%P₂O₅-x SrO (where x = 0, 5 and 10 mol%) quaternary system were synthesized and characterized. The effect of Sr substitutions on bioactivity, proliferation, alkaline phosphatase activity of osteoblast cell line MC3T3-E1 and antibacterial activity were investigated. Dried gels were stabilized at 700 °C to eliminate the nitrates and prevent the crystallization of bioactive glasses. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy results confirmed the formation of hydroxycarbonate apatite on the BG surfaces. The 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and alkaline phosphate activity results showed that 5% SrO increased both differentiation and proliferation of MC3T3-E1 cells, while 10% SrO resulted in a decrease in bioactivity. Live/Dead and DAPI/Actin staining exhibited viable cell and the morphology of actin fibers and nuclei of MC3T3 cells treated with BG-0 and BG-5. The result of antibacterial test showed that strontium substituted 58S BG exhibited antibacterial effect against methicillin-resistant Staphylococcus aureus bacteria. Taken together, results suggest that 58S BG with 5 mol% SrO is a good candidate for bone tissue engineering with maximum cell proliferation and ALP activity, good bioactivity and high antibacterial efficiency.     

Synthesis of some 3-phenyl chromenone-crown ethers and equilibrium studies on complexation with ion-pair extraction of sodium and potassium dyes

6,7-Dihydroxy-3-phenyl-2H-chromenones and 7,8-dihydroxy-3-(methoxyphenyl)-2H-chromenones, o-dihydroxy-3-phenylcoumarins, were prepared from phenylacetic acid/2,4,5-trihydroxybenzaldehyde, methoxyphenylacetic acid/2,3,4-trihydroxybenzaldehyde in NaOAc/Ac₂O, respectively. 3-Aryl-6,7-dihydroxy-2H-chromenone and 3-aryl-7,8-dihydroxy-2H-chromenone reacted with the polyethylene glycol ditosylate in CH₃CN/Me₂CO₃ to afford 12-crown-4,15-crown-5, and 18-crown-6-chromenones. The purified products were identified with IR, ¹NMR, low and high resolution mass spectroscopy and elemental analysis. Liquid–liquid extractive-spectrophotometric studies of sodium and potassium ion complexes of 3a–c, 4a–h coumarin-crown ethers and anionic dyes [4-(2-pyridylazo)-resorcinol monosodium salt monohydrate (SPAR), and sodium picrate (SP), and potassium picrate (PP)], as the counter ion are described. The overall extraction equilibrium constants for the 1:1 complexes of the above coumarin-crown ethers with sodium and potassium ions, between the organic solvent and water, have been determined at 25 °C. They were conducted in various solvent–water systems maintaining an identical initial cation concentration in water, [M₀⁺]_w, and a macrocyclic ligand concentration in the organic phase, [L₀]_org, so that in all extractions [M₀⁺]_w:[L₀]_org ratios were 1:1. An ion association complex formed between the alkali-crown ether complex ion and a dye anion was extracted into the CH₂Cl₂ organic solvent, and then the dye concentration of the separated aqueous phase was measured with an ultraviolet–visible spectrophotometer. According to the study, SPAR is the best associated dye with all the coumarin-crown ethers and the extracted dye occurs as the ion-pair complex. The extraction selectivity was interpreted quantitatively by the constituent equilibrium constants, i.e. K_ext, the ion-pair extraction constant of ML⁺ and A⁻ in CH₂Cl₂.     

PAN/PVC共混膜的制备及性能研究

以N,N-二甲基乙酰胺（DMAC）为溶剂,制备了不同质量百分比的聚丙烯腈（PAN）和聚氯乙烯（PVC）共混溶液,并采用异相成膜法制备PAN/PVC共混薄膜,研究了共混膜中PAN与PVC的共混比例对其相转变行为的影响因素.结果发现当PAN为分散相时,共混膜相分布均匀,PAN相尺寸较小且相边缘较模糊;而当PAN为连续相时,共混膜出现明显空洞,PAN/PVC发生明显相分离,两者几乎不相容.在此基础上,作者还研究了相容剂聚乙二醇（PEG）对PAN/PVC共混物相容性的影响,结果表明,加入PEG后的共混物较未加PEG的共混物相容性有明显改善.     

Renewable-surface sol-gel derived carbon ceramic-modified electrode fabricated by a newly synthesized polypyridil and phosphine Ru (II) complex and its application as an amperometric sensor for hydrazine

A chemically modified carbon ceramic composite electrode (CCE) containing Dichloro{(8, 9-dimethyl-dipyridio [2,3-a;2′,3′-c] phenazine-κ²-N,N′) bis(triphenylphosphine-κ-P)}ruthenium (II) complex which synthesized newly was constructed by the sol-gel technique. Electrochemical behavior and stability of modified CCE were investigated by cyclic voltammetry. The electrocatalytic activity of CCE was investigated and showed a good effect for oxidation of hydrazine in phosphate buffer solution (PBS). A linear concentration range of 6 μM to 1.2 mM of hydrazine with an experimental detection limit of 1 μM of hydrazine was obtained. The diffusion coefficient of hydrazine and its catalytic rate constant for electrocatalytic reaction along with the apparent electron transfer rate constant (k_s) and transfer coefficient (α) were also determined.The modified carbon ceramic electrode doped with this new Ru-complex showed good reproducibility, short response time (t < 2 s), remarkable long-term stability (>3 month) and especially good surface renewability by simple mechanical polishing.The results showed that this electrode could be used as an electrochemical sensor for determination of hydrazine in real water samples used in Fars Power Plant Station, including its heat recovery steam generator (HRSG) water (at different operational condition), cooling system and clean waste water.     

Structural,morphological, and optical studies of hydrothermally synthesized Nb-added TiO2 for DSSC application

Herein, titanium dioxide (TiO₂) nanoparticles doped with various concentrations (0–7 wt %) of niobium (Nb) are hydrothermally synthesized and used effectively as a photoelectrode for application in dye-sensitized solar cells (DSSCs). The rutile-to-anatase phase transition, accompanied by a change in crystallite size from 23.75 to 9.77 nm, is confirmed via X-ray diffraction (XRD) and Fourier transform (FT)-Raman spectroscopy. In addition, the prepared Nb–TiO₂ nanoparticles exhibit a spherical morphology with a mean grain diameter of 43.38–50.69 nm. Further, X-ray photoelectron spectroscopy (XPS) indicates a shift in the Fermi level of the TiO₂ towards the conduction band minimum, and an increase in the bandgap from 2.69 to 2.88 eV, with increasing Nb concentration. The resulting increases in the short-circuit current density (J_SC) and open circuit voltage (V_OC) with the increased injection and conductivity of electrons lead to the enhancement of the DSSC performance. EIS measurements represents the effect of Nb doping on charge transporting and recombination behavior of DSSCs. Moreover, the Nb–TiO₂-based DSSCs provide a better power conversion performance as compared to that of the pristine TiO₂.     

Impregnation synthesis of a novel macroporous silica-based crown ether polymeric material modified by 1-dodecanol and its adsorption for strontium and some coexistent metals

4,4′,(5′)-Di-(tert-butylcyclohexano)-18-crown-6(DtBuCH18C6) is a chelating agent having high selectivity mostly for Sr(II). To significantly reduce its leakage by molecular modification, a macroporous silica-based DtBuCH18C6 polymeric composite (DtDo/SiO₂–P) was synthesized. It was performed by impregnating and immobilizing DtBuCH18C6 and 1-dodecanol molecules into the pores of the SiO₂–P particles utilizing an advanced vacuum sucking technique. The adsorption of a few fission and non-fission products Sr(II), Ba(II), Cs(I), Ru(III), Mo(VI), Na(I), K(I), Pd(II), La(III), and Y(III) onto DtDo/SiO₂–P was investigated. It was done by examining the effects of contact time and the HNO₃ concentration in a range of 0.1–5.0 M at 298 K. At the optimum concentration of 2.0 M HNO₃, DtDo/SiO₂–P exhibited strong adsorption ability and high selectivity for Sr(II) great over all of the tested elements, which showed very weak or almost no adsorption except Ba(II). Meanwhile, It was found that the quantity of total organic carbon (TOC) leaked from DtDo/SiO₂–P in 2.0 M HNO₃, 187.5 ppm, was lower than 658.4 ppm that leaked from DtBuCH18C6/SiO₂–P, which was not modified. This was ascribed to the effective association of DtBuCH18C6 and 1-dodecanol through intermolecular interaction. The reduction of DtBuCH18C6 leakage by molecular modification with 1-dodecanol was achieved. It was of great benefit to application of DtDo/SiO₂–P in chromatographic partitioning of Sr(II), one of the main heat generators, from high level liquid waste (HLLW) in reprocessing of nuclear spent fuel in the MAREC (Minor Actinides Recovery from HLLW by Extraction Chromatography) process developed recently.     

Effect of Bi contents on key physical properties of NiO NPs synthesized by flash combustion process and their cytotoxicity studies for biomedical applications

Nickel oxide has tremendous applications in the field of biomedicine. In this study, NiO nanoparticles were synthesized with different Bi contents (NiO@Bi; 0.0–7.5 wt%), and multifunctional usages were investigated. Structural confirmation was conducted through XRD and Raman studies, which revealed a monophasic cubic system. With increasing Bi content, broadening of the XRD and Raman peaks were observed, indicating a reduction in particle size. The crystallite size was found to be in the range of 10–26 nm. The decrease in particle size was confirmed through dynamic light scattering measurement. The homogeneous distribution of all elements and the presence of Bi were detected by an EDX/SEM e-mapping study. Field emission electron microscopy confirmed the formation of spherical shape nanoparticles. The grain size was reduced from 30 nm to 10 nm with Bi content, in accordance with XRD and Raman results. The Kubelka-Munk method was employed to determine the effect of Bi content on the optical band gap of NiO. The energy gap was reduced with Bi content in the range of 3.32–3.50 eV. Antimicrobial and in vitro cytotoxic characteristics of the prepared NPs were also studied. The results revealed that all NiO@Bi NPs had negligible antimicrobial activity and no cytotoxic effects on both normal and activated splenic cells. The in vivo acute cytotoxicity study indicated no cytotoxic effects on liver and kidney functions. The prepared NiO@Bi NPs were implanted in living organisms without hepatic/renal toxicity, demonstrating excellent biocompatibility, cell viability, and superior quality of nanocrystals, suggesting that the prepared NPs are ideal candidates for antibacterial and biomedical applications.     

Voltammetric studies of a novel bicopper complex modified glassy carbon electrode for the simultaneous determination of dopamine and ascorbic acid

A novel modified glassy carbon electrode (GCE) with a binuclear copper complex was fabricated using a cyclic voltammetric method in phosphate buffer solution. This modified electrode shows very efficient electrocatalytic activity for anodic oxidation of both dopamine (DA) and ascorbic acid (AA) via substantial decrease in anodic overpotentials for both compounds. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) using this modified electrode show two well-resolved anodic waves for the oxidation of DA and AA in mixed solution, which makes it possible for simultaneous determination of both compounds. Linear analytical curves were obtained in the ranges 2.0–120.0 μM and 5.0–160.0 μM for DA and AA concentrations by using DPV methods, respectively. The detection limits were 1.4 × 10⁻⁶ M of DA and 2.8 × 10⁻⁶ M of AA. This electrode was used for AA and DA determinations in medicine and foodstuff samples with satisfactory results.     

Synthesis and characterization of novel poly(γ‐benzyl‐L‐glutamate) derivatives tailored for the preparation of nanoparticles of pharmaceutical interest

Four poly(γ‐benzyl‐L ‐glutamate) (PBLG) derivatives bearing at one end specific groups were synthesized by ring‐opening polymerization of the corresponding γ‐benzyl‐L ‐glutamate N‐carboxyanhydride using different amine‐terminated initiators. These moieties were chosen to introduce, on demand, specific functionalities in nanoparticles of pharmaceutical interest. The PBLG and PBLG derivatives were characterized by ¹H NMR, viscosimetry, Fourier transform infrared spectroscopy and differential scanning calorimetry. Nanoparticles smaller than 100 nm in diameter could be easily prepared from these PBLG derivatives by slight modification of a known nanoprecipitation technique. Copyright © 2006 Society of Chemical Industry     

Synthesis and characterization of a new iridium(III) complex with bulky trimethylsilylxylene and applications for efficient yellow-green emitting phosphorescent organic light emitting diodes

We designed and synthesized a new iridium(III) complex with phenylpyridine ligands containing a bulky trimethylsilylxylene, 5-(2,5-dimethyl-4-(trimethylsilyl)phenyl)-2-phenylpyridine, by Suzuki coupling reaction and characterized using various spectroscopic studies. Nuclear magnetic resonance studies show its structure to be that of a facial isomer. Thermogravimetric analysis and differential scanning calorimetry studies show its higher thermal stability (?T_5%) of 638 K with a glass transition temperature of 425 K. It shows the photoluminescence emission at 532 nm in solution with the band gap energy of 2.56 eV. The new iridium(III) complex as dopant in phosphorescent organic light emitting diodes exhibits the yellow-green emission at 532 nm as it effectively hinders aggregation formation in the solid state at a dopant concentration of 6%, resulting in higher device efficiencies of 12.7% and 45.7 cd/A. The results show that the new iridium complex could be useful in white organic light emitting diodes for the lighting applications.     

Binder-less fabrication,some surface studies,and enhanced electrochemical performance of Co,Cu-embedded MnO2 thin film electrodes for supercapacitor application

We report the fabrication of nanocystalline MnO₂ thin film-based electrode on a predeposited indium tin oxide (ITO) film on the glass substrate, using a binderless and simple two-electrode electrofabrication approach. Effects of Co and Cu incorporation on microstructural and electrochemical performance of the electrode were optimally and extensively investigated. The experimental results for the optimum fabrication conditions for Co@MnO₂ and Cu@MnO₂ and pure MnO₂ thin film-based electrode samples showed uniqueness in microstructural features, degrees of crystallinity and roughness, and high electrochemical energy storage performance. Co@MnO₂ film electrode exhibited remarkable specific capacitance (1068 Fg^-1) and areal capacity (25.78 mAh cm^?2) as against other electrode films (Cu@MnO₂ and pure MnO₂) which exhibited specific capacitances 837 and 438 F g^?1 and areal capacities 10.6 and 4.9 mAh cm^?2, respectively. Exceptional stabilities were also recorded for the composite samples (87.2% and 84.4% for Cu@MnO₂ and Co@MnO₂ thin film electrodes, respectively) against the pure MnO₂ film electrode sample (77.8%), after 2000 cycles. In addition, the short time constants (1.27 s and 1.31 s) were respectively realized for the fabricated Co@MnO₂ and Cu@MnO₂ electrode films as against the pure MnO₂ electrodes (4.35 s). These features observed in the composite electrode samples demonstrated an exhibition of faster ion response and higher rate capability by the samples. Moreover, the incorporation of Co into the MnO₂ electrode material relatively improved the supercapacitive activeness by enhancing the charge transition and transport.     

Complexation of Surfactant/β‐Cyclodextrin to Inhibit Surfactant Adsorption onto Sand,Kaolin, and Shale for Applications in Enhanced Oil Recovery Processes. Part I: Static Adsorption Analysis

Surfactant adsorption onto solid surfaces is a major issue during surfactant flooding in enhanced oil recovery applications; it decreases the effectiveness of the chemical injection making the process uneconomical. Therefore, it was hypothesized that the adsorption of surfactant onto solid surfaces could be inhibited using a surfactant delivery system based on the complexation between the hydrophobic tail of anionic surfactants and β‐cyclodextrin (β‐CD). Proton nuclear magnetic resonance spectroscopy was used to confirm the complexation of sodium dodecyl sulfate (SDS)/β‐CD. Surface tension analysis was used to establish the stoichiometry of the complexation and the binding constant (K_a). Static adsorption testing was applied to determine the adsorption of surfactant onto different solids (sandstone, shale, and kaolinite). The release of the surfactant from the β‐CD cavity was qualitatively evaluated through bottle testing. The formation of the inclusion complex SDS/β‐CD with a 1:1 stoichiometry was confirmed. The K_a of the complexations increases as salinity and hardness concentration increases. The encapsulation of the surfactant into the β‐CD cavity decreases the adsorption of surfactant onto solid surfaces up to 79 %. Qualitative observations indicate that in the presence of solid adsorbents partially saturated with crude oil, the β‐CD cavity releases surfactant molecules, which migrate towards the oil–water interface.     

Mixed monolayer and mixed micelle formation in binary mixture of surfactants—Systems for trioxyethylenated dodecyl sulfonate and some polyoxyethylenated fatty alcohol ether nonionic surfactants

The interaction and synergism of some polyoxyethylenated fatty alcohol ether (POE) nonionic surfactants (C₁₂E₂, C₁₂E₃, C₁₀E₅, C₁₀E₇, where C_x indicates number of carbon atoms in the chain and E_y indicates number of oxyethylene glycol ethers) with trioxyethylenated dodecyl sulfonate (C₁₂E₃S) in mixed monolayer formation at the surface and in mixed micelle formation in aqueous solutions were studied at 25 and 40°C by calculating interaction parameters (β_α, β_M) from surface tension-concentration data by use of Rosen's equations based on the nonideal solution theory. All the systems investigated adapt reasonably well to the nonideal model, with negative values of β_σ and β_M (where M means micelle and σ refers to the air-liquid interface) indicating a favorable interaction between the mixed surfactants. Either at a monolayer or in a mixed micelle, the attractive interaction becomes stronger when the alkyl chain in the POE surfactant is longer, i.e., when the POE becomes more hydrophobic. The interaction increases in the order C₁₀E₇<C₁₀E₅<C₁₂E₃, C₁₂E₂. For the two C₁₀E _n (n= 5,7)/C₁₂E₃S systems, as temperature increases from 25 to 40°C, the interaction increases in a mixed micelle, but it decreases in a mixed monolayer. Synergism in mixed micelle formation exists for C₁₂E₃S/C₁₀E _n mixtures when X₁ ^M , the mole fraction of POE in a mixed micelle, is ≈0.4–0.8, whereas synergism does not occur in the systems of C₁₂E₃S/C₁₂E _m due to the large difference between CMC₁ and CMC₂, i.e., large |In(C ₁ ^M /C ₂ ^M )| value (where CMC=critical micelle concentration). The degree of synergism in mixed micelle formation is temperature independent and is 0.23, 0.18, and close to zero for C₁₀E₅/C₁₂E₃S, C₁₀E₇/C₁₂E₃S, and C₁₂E _m (m=2,3)/C₁₂E₃S systems, respectively. Synergism in surface tension reduction effectiveness occurs in C₁₂E₃S/C₁₂E₂ and C₁₂E₃S/C₁₂E₃ systems. The mole fractions of POE in the solution phase are 0.302 and 0.333 for the two mixtures at the point of maximum synergism.