The LB Films of Dansyl Chloride Labeled Octadecylamine and Its Fluorescence Lifetime

IntroductionFluorescent probe labeling 1, 2, microchip and LB (Langmuir-Blodgett) films of DNA and proteins3 are important in molecular electronic and biotechnological applications such as information processing and molecular recognition. As an imitated and simplified model of above complex cases, here we prepare the LB films of dansyl chloride (5-dimethylaminonaphthalene-1-sulfonyl chloride, denoted as DNS) labeled octadecyl amine (AM). A molecule based naphthalene sulfonate is well kno…     

Electrically Detaching Behavior and Mechanism of Ionic Conductive Adhesives

Design of rapidly detachable adhesives with high initial bonding strength is of great significance but it is full of great challenge. Here,we report the fast electrically detaching behavior(100% detaching efficiency in just 1 min under dozens of DC voltage) and high initial bonding strength(>12 MPa) of epoxy-based ionic conductive adhesives(ICAs). The epoxy-based ICAs are fabricated by introducing polyethylene glycol dimethyl ether(PEGDE) and 1-ethyl-3-methylimidazolium trifluoromethanesulfon...     

Study on Synthesis and Intercalation Behavior of Layered Zirconium Proline-N-methylphosphonate-phosphate

Zirconium proline-N-methylphosphonate-phosphate (α-ZPMPP) was prepared in the presence of HF for the first time. The α-ZPMPP sample is highly crystallized with interlayer distance of 1.52nm. The interlayer distance of complex of α-ZPMPP with n-butylamine (α-ZPMPP-BA) is in 0.45 nm larger than that of α-ZPMPP. The α-ZPMPP possesses different intercalation behavior of host-guest compound from α-ZP.     

Critical Behavior of Binary Mixtures of Nitrobenzene?+?n-Undecane and Nitrobenzene?+?n-Dodecane

Turbidities and isobaric heat capacities per unit volume, in a wide temperature range, have been measured for critical binary solutions of {nitrobenzene?+?n-undecane} and {nitrobenzene?+?n-dodecane}. The critical exponents and the system-dependent critical amplitudes were deduced. The non-critical and the critical-fluctuation induced contributions to the background heat capacities were determined. We also obtained the coupling constant $ \bar{u} $ by analyzing the coexistence curve data with crossover theory. These parameters were used to test some universal amplitude ratios and together with the coexistence-curve data to test the complete scaling theory. It is shown that the contribution from heat capacity plays an important role in describing the asymmetric criticality of the coexistence curve.     

Solution and Diffusion Behavior of Pure Gases and Gas Mixtures in Glassy Polymer Membranes

A general model for the solution and diffusion behavior in pure gas-polymer membrane systems and gas mixture-polymer membrane systems has been developed. Proved by experiments on different glassy and rubbery polymer membranes at various temperatures and pressures, this model can achieve the prediction of permeation behavior of pure gases and gas mixtures in polymer membranes only using the model parameters obtained from experiments on pure gases. The calculated results are in good agreement with experimental.     

The Chemical Speciation and Behavior of Mercury and Selenium in the Insoluble Fraction of Striped Dolphin Liver

Most of the mercury and selenium exist in the insoluble fraction of dolphin liver. After the insoluble fraction was digested by alkaline protease in the presence of 1% SDS, approximately 50% of Hg and Se consisted in the supernatant and the others in the residue. Gel filtration chromatography of the hydrolysate showed that 96% of Hg and 87% of Se were combined with the high molecular weight proteins stably, which cannot be substituted by the complex reagents.Mercury and selenium in the residue were confirmed as HgSe crystal.     

Valence Bond Study of Dissociation Behavior and Spectroscopic Constants for the Ground States of LiF and NaF

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Effect of Oxygen on Surface Properties and Drug Release Behavior of Plasma Polymer of n-Butyl Methacrylate

The effects of oxygen on the chemical structure, morphology, hydrophilicity and drug release behavior of radio-frequency plasma poly n- butyl methacrylate （PPBMA） thin film were carded out for the first time. ATR-FTIR and XPS showed that oxygen had little influence on the chemical structure and composition of PPBMAs, which did not agree with the thought that the presence of oxygen gas would increase the oxidized carbon functionalities in the plasma polymer. SEM and static contact angle measurement indicated that in case of deposition with oxygen, the smoothness and hydrophilicity of PPBMA were dramatically improved. The drug release behavior showed that drug release from the PPBMA coating without oxygen was biphasic patterns, while from PPBMA coating with oxygen was Higuchi release. These results were helpful for the design and tailoring of the PPBMA polymer film and other of plasma polymers film, but could provide a new idea for the drug release controlled form.     

Synthesis and Characterization of Monomeric Salicylaldiminato Lanthanide Complexes and Their Catalytic Behavior for Polymerization of ε—Caprolactone

IntroductionSchiffbaseligandscanbeusedtoprovideastereochem icallyrigidligandframeworkinhomogenousprecatalystsofsomemetals,suchassalenCrcatalystsinasymmetricring openingreactionofepoxide1andsalenAlinring openingpolymerizationoflactideandrelatedcyclicesters .2 Recently ,itwasreportedthatthebidentateSchiffbasecomplexesofearlyandlatetransitionmetalscanserveaspromisingalterna tivestometallocenecatalystsforthepolymerizationofα olefins.3Therefore ,theapplicationsofSchiffbaseligandsinorganometallic…     

Adsorption Behavior of Lysozyme and Tween 80 at Hydrophilic and Hydrophobic Silica–Water Interfaces

Nonionic surfactants such as Tween 80 are used commercially to minimize protein loss through adsorption and aggregation and preserve native structure and activity. However, the specific mechanisms underlying Tween action in this context are not well understood. Here, we describe the interaction of the well-characterized, globular protein lysozyme with Tween 80 at solid–water interfaces. Hydrophilic and silanized, hydrophobic silica surfaces were used as substrates for protein and surfactant adsorption, which was monitored in situ, with ellipsometry. The method of lysozyme and Tween introduction to the surfaces was varied in order to identify the separate roles of protein, surfactant, and the protein–surfactant complex in the observed interfacial behavior. At the hydrophobic surface, the presence of Tween in the protein solution resulted in a reduction in amount of protein adsorbed, while lysozyme adsorption at the hydrophilic surface was entirely unaffected by the presence of Tween. In addition, while a Tween pre-coat prevented lysozyme adsorption on the hydrophobic surface, such a pre-coat was completely ineffective in reducing adsorption on the hydrophilic surface. These observations were attributed to surface-dependent differences in Tween binding strength and emphasize the importance of the direct interaction between surfactant and solid surface relative to surfactant–protein association in solution in the modulation of protein adsorption by Tween 80.     

The Adsorption Behavior of Lithium Cationon Polyacene and Its Influenceon Conductive Property

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The Electrochemical Behavior and the Determination of Bavistin on Glassy Carbon Electrode

Bavistin(MBC)'isatypeofveryimportantbactericides.Theanalyticalmethodsofthispesticideincludingchromatography',polarography'havebeenreported,butthereisnoreportaboutthedetendnationwithvoltanuntryonglassycarbonelectrode.Inthispaper,westudiedthevoltanunetric(CV)propertiesandthedifferentialpulsestrippingvoltanunetry(DPSV)detendnationofMBConglassycarbonelectrode.TheinstrUmentusedinthisexperimentwastheBAS-l(X)AElectroanalyser.Aglassycarbonelectrodewasusedastheworkingelectrode,aconunercialAgjA…     

Preparation and Photochromic Behavior of Novel Hybrid Inorganic—Organic Thin Film

A novel photochromic complex comprising of Keggin type tungstophosphate acid (PW12) and polyacrylamide(PAM) was prepared. FT-IR results showed that the Keggin geometry of PW12 was still preserved inside the composite, and a charge-transfer bridge was built between pw12 and PAM via hydrogen bond. AFM images indicated that surface topography of polymer matrix changed after adding PW12. Under UV irradiation, the film was reduced photochemically to yield a blue species, which was reversible in the present of oxygen in polymeric network.     

Phase Chemistry and Thermochemstry on Coordination Behavior of Zinc Chloride with Leucine

The solubility property of the ZnCl2-Leu-H2O(Leu=L-a-leucine) system at 298.15K in the whole concentration range was investigatey by the semimicro-phase equilibrium method.The corresponding solubility diagram and refractive index diagram were constructed.The results indicated that there was one complex formed in this system.namely,Zn(Leu)Cl2.The complex is congruently soluble in water.Based on Phase equilibrium data,the complex was prepared.Its composition and properties were characterized by chemical analysis,elemental analysis,IR spectra,and TG-DTG.The thermochemical properties of coordination reaction of zinc chloride with L-a-leucine were investigated by a microcalorimeter.The enthalpies of solution of L-a-leucine in water and its zinc complex at infinite dilution and the enthalpy change of solid-liquid reaction wrer determined at 298.15K.The enthalpy change of soild phase reaction and the standard enthalpy of formation of zinc complex were claculated.On the basis of experimental and calculated results,three thermodynamic parameters(the activation enthalpy,the activation entropy and the activation free energy),the rate constant and three kinetic parameters(the activation energy,the preexponential constant and the reaction order) of the reaction,and the standard enthalpy of formation of Zn(Leu)^2 (aq) were obtained.The results showed that the title reaction took place easily at studied temperature.     

Synthesis of Bowl-like Particles by Emulsion Polymerization and Release Behavior of Solvent from the Particles

Bowl-like poly (styrene-co-glycidyl methacrylate) was synthesized by swollen seeded emulsion polymerization. The polymerization was carried out in PS seed emulsion swollen by toluene, whereby the bowl-like particles formed at last. The shape was observed by SEM. These particles became ball-like when swollen by toluene, observed by optical microscope, and the release behavior of solvent from them was examined.     

Synthesis and Characterization of Benzimidazolium Salts as Novel Ionic Liquids and their Catalytic Behavior in the Reaction of Alkylation

A new series of ionic liquids have been prepared containing benzimidazolium cation (abbreviated as Bim). These salts were characterized by DSC, NMR, elemental analysis and thermogravimetric analysis. They showed different properties compared to imidazolium cation due to the introduction of benzene ring. The alkylation of benzene/diphenyl ether with 1-dodecene was carded in C4eBimBr-AlCl3 ionic liquids showing high catalytic activity when the mole ratio of C4eBimB:AlCl3 was 1:2.     

Synthesis and Phase Behavior Studies of Two New Chiral Liquid Crystals of Schiff Base——The Influence of Intramolecular Hydrogen Bond on the Phase Behavior

Two new chiral liquid crystals of schiff-base type have been synthesized.This series of compounds contain α-chloro acidic ester chain prepared from commercially available L-valine.Both of the compounds exhibit tilted smectic phases;their phase transitions were studied using DSC and polarized optical microscopy;the influence of intramolecular hydrogen bonds on the phase behavior was studied as well.     

Behavior of triazines upon γ-irradiation

The behavior of triazines upon -irradiation from a⁶⁰Co source has been studied. The triazines selected were: atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine], ametryne [2-ethylamino-4-(isopropylamino)-6-(methylthio)-s-triazine] and simazine [2-chloro-4,6-bis(ethylamino)-s-triazine]. The irradiation doses varied from 5.0 to 640.0 kGy, with a dose rate of 3 kGy h^–1. Following irradiation, the samples were analyzed by gas chromatography with flame ionization (FID) detection. The triazines remained stable after the irradiation process.     

Anionic Polymerization Behavior of α-Methylene-N-methylpyrrolidone

Anionic polymerization of α-methylene-N-methylpyrrolidone ( MMP ) was carried out in THF at −78∼0 °C with diphenylmethylpotassium (Ph₂CHK) and with diphenylmethyllithium (Ph₂CHLi) in the presence of Lewis acidic diethylzinc (Et₂Zn). Poly( MMP )s possessing predicted molecular weights based on the molar ratios between monomer and initiators and narrow molecular weight distributions (M_w/M_n < 1.1) were obtained in quantitative yields. It was demonstrated that the propagating chain end of poly( MMP ) was stable at −30 °C to form the polymers with well-defined chain structures. From the polymerizations at the various temperatures ranging from −50 to −30 °C, the apparent rate constant and the activation energy of the polymerization were estimated as follows: ln k = −6.93 × 10³/T + 25.7 and 57 ± 5 kJ mol⁻¹, respectively.