苄氧基甲基12-冠-3的合成与锂离子选择性电极研究

报道了苄氧基甲基－１２－冠－３的合成，并以此化合物作载体研制成锂离子选择电极。用苄氧基甲基－１２－冠－３为载体的电极对锂离子响应的线性范围为１．０ × １０－１～８．３× １０－５ｍｏｌ／Ｌ；检测限为４．２ × １０－５ ｍｏｌ／Ｌ，斜率为５７．４ ｍＶ／ｐＬｉ（２５℃）。电极具有好的稳定性和重现性。电极用于人工试样锂含量测定，结果与原子吸收光度法基本一致。

A New Cytotoxic Sterol Produced by an Endophytic Fungus from Castaniopsis fissa at the South China Sea Coast

A new sterol, ergosta-8(9),22-diene-3,5,6,7-tetraol(3β,5α,6β,7α,22E)(A) together with three known sterols: 3β, 5α,6β-trihydroxyergosta-7,22-diene (B), 3β-hydroxy-5α,8α- epidioxyer-gosta-6,22-diene (C) and ergosterol (D) were isolated from the mycelia of an unidentified endophytic fungus separated from Castaniopsis fissa (chestnut tree). Compound A exhibited potent selective cytotoxicity against Bel-7402, NCI4460 and L-02 cell lines with IC50 values 8.445, 5.03, 13.621 μg/mL, respectively.

Rapid treatment of atrazine-contaminated water by nickel/iron bimetallic system

The utility of nickel/iron in the remediation of atrazine-contaminated water was investigated. The experimental results showed that nickel/iron had effective catalytic activity in dechlorinating atrazine under acidic conditions. The dechlorination reaction approximately followed the first-order kinetics under the experimental conditions(nickel/iron:1.0 g/250 ml;C atrazine=20.0 mg/L), the reaction rate increased with decreasing pH value of the reaction solution and increasing the proportion of Ni:Fe within 2.95%. For condition with 2.95% nickel/iron, the reaction rate constants were 0.07518(R=0.9927), 0.06212(R=0.9846) and 0.00131 min -1(R=0.9565) at pH=2.0, 3.0 and 4.0, respectively. HPLC analysis was used to monitor the decline of atrazine concentration.

THE PREPARATION AND CHARACTERIZATION OF SBR/PS CORE-SHELL PARTICLES BY GAMMA IRRADIATION

A kind of core(SBR)-shell(PS)particles was synthesized by using SBR latex and grafting with St under gammairradiation.The influences of absorbed dose and dose rate on the grafting yield of PS on SBR seed latex have beeninvestigated.Results show there was a transition layer which contained the SBR/PS graft copolymer between the SBR coreand PS shell.Dynamic laser scattering(DLS)and differential scanning calorimetry(DSC)results confirm the existence ofgrafted polystyrene,and transmission electron microscope(TEM)observation verifies the core-shell structure of SBR-g-PSlatex.Such SBR/PS core-shell latex could be processed easily to ultrafine rubber powders by using spray drying andexpected to be used as an impact modifier for PS.

Finding of Gray Points on the Surface of the Sn-Fe Alloy Layer and Its Effects on the Corrosion Resistance of the Alloy Layer

After removing tin coating of tinplates offered by some steel works, we discovered massive, highly disperse gray points outspreading along rolling direction on the surface of the alloy layer. Morphology of the alloy layer was observed by scanning electron microscope (SEM), and many cavities of the alloy layer were found out in the gray point. After analyzing the composition of the alloy layer, we found that content of Fe in the gray points was more than that in the normal alloy layer. Moreover, corrosion resistance of the alloy layer declines with increase of amount of gray points. In addition, the hot-humidity testing was carried out for some plates whose surface has many gray points. After 14 days, there were many rust points occurring in the edge of gray points and in the small gray points. The morphology of rust points was observed by atomic force microscope (AFM). The reason why rust points generated in the edge of gray points and in the small gray points was discussed.

A New Approach for Removal of Nitrogen Oxides from Synthetic Gas-streams under High Concentration of Oxygen in Biofilters

The potential of using denitrifying and nitrifying concurrent biofilters for the removal of nitrogen oxides from synthetic gas streams was studied under the condition of high oxygen concentration. It was found that more than 85% of nitric oxide was removed from synthetic combustion gas-streams which contained 20% oxygen and 350 μL/L NO, with a residence time of 60 seconds. In the process, it was found that the existing of oxygen showed no evident negative effect on the efficiency of nitrogen removal.

Synthesis of Novel Benzoylphenylurea Chitin Inhibitors from Chlorothalonil

Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation reactions.

Phase Behavior of Rare Earth Manganites

Among complex oxides containing rare earth and manganese BaLn_2Mn_2O_7 (Ln=rare earth) with the layered perovskite type and Ln_2(Mn, M)O_7 with pyrochlore-related structure were studied since these compounds show many kinds of phases and unique phase transitions. In BaLn_2Mn_2O_7 there appear many phases, depending on the synthetic conditions for each rare earth. The tetragonal phase of so-called Ruddlesden-Popper type is the fundamental structure and many kinds of deformed modification of this structure are obtained. For BaEu_2Mn_2O_7 at least five phases have been identified from the results of X-ray diffraction analysis with the space group P4_2/mnm, Fmmm, Immm and A2/m in addition to the fundamental tetragonal I4/mmm phase. In the pyrochlore-related type compounds, Ln_2Mn_(2-x)M_xO_7 (M=Ta, Nb, W etc), there also appear several phases with different crystal structures. With regard to every rare earth, Ln_2MnTaO_7 phase is stable only for excess Ta and can be obtained under high oxygen partial pressure process. This group has trigonal structure with zirkelite type (P3_121 space group). On the other hand Ln_2Mn_(2/3)Nb_(4/3)O_7 phase has monoclinic (C2/c space group) and zirconolite type structure. All of these structural models have the fundamental structure based on HTB (hexagonal tungsten bronze) layers formed by the arrangement of oxygen octahedra.

Secondary Activation of Commercial Activated Carbon and its Application in Electric Double Layer Capacitor

The cheap commercial activated carbon (AC) was improved through the secondary activation under steam in the presence of FeCl2 catalyst in the temperature range of 800-950℃ and its application in electric double layer capacitors (EDLCs) with organic electrolyte was studied. The re-activation of AC results in the increases in both specific capacitance and high rate capability of EDLCs. For AC treated under optimized conditions, its discharge specific capacitance increases up to 55.65 F/g, an increase of about 33% as compared to the original AC, and the high rate capability was increased significantly. The good performances of EDLC with improved AC were correlated to the increasing mesoporous ratio.

Synthesis and Properties of Gemini Cationic Surfactants with Amide Spacers

Four gemini cationic surfactants {N,N′-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s=2,3,4,6} were synthesized by using four bis(α-chloroacetamide)s and N,N-dimethyllaurylamine, respectively. The molecular structures were characterized by means of IR, ~ 1H NMR, \{~ ~13 C NMR\} and MS, and the behavior of their aqueous solutions was studied. The critical micell concentrations(CMC) of LAA-s-LAA were one order of magnitude lower than that of dodecyltrimethyl ammonium chloride(DTAC). With the change of the length of spacer chain(s), their CMC values change, and CMC reaches the top value at s=4.

Researches on Formation of Haloacetic Acids in Chlorination of Drinking Water by a Novel Technique

Haloacetic acids(HAAs) are formed during the chlorination of drinking water,which are harmful to people′s health due to their carcinogenic and mutagenic effects. In the present study,a detection method combining methyl tert -butyl ether(MtBE) extraction with acid catalysis and gas chromatography coupled with an electron capture detector(GC/ECD) was developed for determining HAAs. The detection limit of this method(MDL) and relative standard deviation(RSD) were below 0.37 μg/L and 6.2%,respectively. The laboratory chlorination experiments were conducted with the purpose of investigating the influences of reaction time,temperature,UV_ 254 ,bromide and ammonia-nitrogen on the formation of HAAs. The results show that the formation amount of HAAs increases with increasing reaction time and temperature,respectively;and there exists a linear relationship between the formation of HAAs and UV_ 254 . The formation amount of HAAs decreases first and then increases as the bromide ion concentration increases,and adding NH +_4 is a possible way to control the formation of HAAs.

Adsorption of β-naphthalenesulfonic acid/sulfuric acid from their solution by weakly basic resin:equilibrium

Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of β-naphthalenesulfonic acid(NSA) and sulfuric acid (H_2SO_4) from their solution at 25℃ onto weakly basic resin D301R. Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The ideal adsorbed solution theory(IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria. The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA, respectively, yields the favorable representation of the bisolute competitive adsorption behavior.

Effect of Cold Plasma Treatment on the Mechanical Properties of RTM Composites

Cold plasma technology was used to treat the surface of carbon fibers braided by PET in this paper and SEM was used to analyze the fracture microstructure of composite interlaminar shear stress (ILSS). The result shows that the surface polarity of carbon fibers was modified by cold plasma treatment, which increases the impregnation of PET braided carbon fibers during the process of resin flowing, improves the interfacial properties of RTM composites, and therefore enhances the mechanical properties of the KTM composites.

A Simple Model to Determine the Trends of Electric Field Enhanced Water Dissociation in a Bipolar Membrane

This work is concentrated on elucidating the mechanism of the electric field enhanced water dissociation. A simple model was established for the theoretical current-voltage characteristics in water dissociation process on a bipolar membrane based on the existence of a depletion layer and Onsager's theory. Particular attention was given to the influence of applied voltage on depletion thickness and the dissociation constant. The factors on the water splitting process, such as water diffusivity, water content, ion exchange capacity, temperature, relative permittivity, etc. Were adequately analysed based on the derived model equations and several suggestions were proposed for decreasing the applied voltage in practical operation. The water dissociation tests were conducted and compared with both the theoretical calculation and the measured current-voltage curves reported in the literature, which showed a very good prediction to practical current-voltage behavior of a bipolar membrane at high current densities when the splitting of water actually commenced.

A Novel Catalyst for Liquid Phase Hydrogenation of m-Dinitrobenzene to m-Phenylenediamine

A novel lanthana-promoted nickel catalyst supported on silica for the liquid phase hydrogenation of m-dinitrobenzene to m-phenylenediamine was prepared by an incipient wetness sequential impregnation method. It was found that Ni-La/SiO2 catalyst exhibited high activity and stability for m-dinitrobenzene hydrogenation. Over this catalyst, the conversion of m-dinitrobenzene and the yield of m-phenylenediamine were up to 97.1% and 93.5%, respectively, at 373 K and 2.6 MPa hydrogen pressure after reaction for 1 h.

Photoelectrochemical Properties of Highly Oriented ZnO Nanotube Array Films on ITO Substrates

Highly oriented ZnO nanotube array films on the conducting substrates have been synthesized by a simple hydrothermal method and characterized by scanning electron microscopy (SEM) and UV-Vis spectroscopy. The thin films consisting of laterally fragmentized ZnO nanotubes with controlled orientation have been tested as photoanode in Gr鋞zel-type solar cell. For a sandwich-type cell, with 0.5 mol/L LiI and 0.05 mol/L I2 in propylene carbonate electrolyte, the overall solar energy conversion efficiency reaches 2.3%.

Preparation and Crystal Structure of Sodium Hydrogen Epoxysuccinate

C4H3O5Na(0.5H2O) was prepared by the reaction of H2O2 and maleic anhydride. The product was characterized by elemental analysis and IR measurement. The crystal structure was determined by single-crystal diffraction analysis. The crystal belongs to monoclinic, space group C2/c with a = 21.132(3), b = 8.646(2), c = 6.196(1) ?, β = 90.67(1)o, V = 1132.0(4) ?3, Mr = 163.06, Dc = 1.914 g/cm3, Z = 8, F(000) = 664, μ = 0.243 mm-1, the final R = 0.0354 and wR = 0.1151. X-ray analysis reveals that there exists a stable symmetrical structure in the complex, and a network structure is formed via intermolecular hydrogen bonds.

Two Cyclic Peptides Produced by the Endophytic Fungus # 2221 from Castaniopsis fissa on the South China Sea Coast

New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-Val-L-Leu-L-Val-L-Leu) and cyclo(L-Leu-L-Ala-L-Leu-L-Ala), respectively.

Two New Ionone Derivatives from Rhododendron przewalskii Maxim.

Two new ionone derivatives, named rhododendrone and rhododendronside, were isolated from the alcoholic extract of the aerial parts of Rhododendron przwalskii Maxim. Their structures were elucidated on the basis of spectroscopic analysis

A New Synthetic Route to 12-Oxo-1,15-pentadecanlactam

Oxo-1, 15-pentadecanlactam 7 was synthesized from cyclododecanone with a total yield of 36% in a seven-step reaction. The azide 5 to 12-nitro-1, 15-pentadecanlactam 6 is the key step featured by direct ring expansion.