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1.
Yanshan Petrochemical Company,Ltd.has recently transferred all the equity itholds in Yanhua High-Tech(000609).Furthermore,another listed company inSinopec Corp.has completed assetreformation.According to market  相似文献   

2.
The High Performance Liquid Chromatography (HPLC) method is employed with copolyamide-170 (PA-170) membrane material as packing to determine the retention volume (V?R) and equilibrium distribution coefficient (K?A) of both inorganic solutes and organic solutes. Based on the experimental data, the interfacial parameters of the packing material are obtained.  相似文献   

3.
Proton transfer reactions between zeolite Y surface and 1-naphthylamine (NA) in the ground and excited states have been studied by laser-induced picosecond spectroscopy. The acidic form of zeolite Y readily protonates NA in the ground state. At low acid strength of the zeolite the excited state of the protonated NA transfers back the proton to the zeolite surface as indicated by the fluorescence spectra. At high acid strength of the zeolite the fluorescence comes from the protonated form of NA and from an adduct X previously found in highly concentrated HClO4 solutions. The concentrations of the protonated NA and X increase with the reduction in the unit cell size. The presence of these species is discussed in terms of the next nearest neighbor NNN theory of zeolite Y acidity and the role of the non-framework aluminum. The acidity of the zeolite is estimated, based on the fluorescence lifetimes of X, to vary from 3.7 to 17 M HClO4 depending on the unit cell size. Low loading levels of NA in the zeolite pores are best in studying the proton transfer reaction and for the estimation of the surface acidity of zeolite Y.  相似文献   

4.
Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted solution. The influences of temperature, phase volume ratio (PVR), concentration of sodium Dodecyl benzene sulphonate and pH value etc. on the extraction efficiency were examined. It is found that, compared with traditional extraction techniques under the same condition, a higher extraction productivity can be obtained by PDSE. The stability of colloidal liquid aphrons plays an important role in this process. In a certain scope, the extraction efficiency increases with PVR. Excessive amount of solvent is not much helpful. A new analytical method by using ultraviolet spectrometer to determine the concentration of quercentin is established.  相似文献   

5.
A new kind of electrophoretic affinity chromatography (EAC) for bioseparation was proposed,Separation by EAC was conducted in a multicompartment electrolyzer in which the affinity gel media were packed in one of the central compartments.The presence of an electric field accelerated the migration of proteins inside the gel matrix during adsorption and descrption processes,This led to the increase of the overall speed of separation,The present study was focused on the effect of the strength of the electric field on adsorption and desorption processes.  相似文献   

6.
The oligomerization of octene-1 was studied in the presence of zeolites of different structural types (e.g., Y, Beta, ZSM-12, and ZSM-5). It was shown that at 150–200°C, wide-pore zeolite catalysts Y, Beta, and ZSM-12 exhibit high catalytic activity in the reaction. The conversion of catalyzed octene can be as high as 96%, and the yield of oligomers is 88–100 wt %. Zeolite ZSM-5 at 150–180°C has low activity and mainly catalyzes the isomerization of octene-1. As the temperature rises to 250°C, low molecular weight oligomers resulting from the cracking process are the main products of this reaction. The activity and selectivity of zeolite catalysts in the oligomerization of octene-1 are conditioned by their acidic properties and structural characteristics, as well as by the reaction conditions. It was revealed that the main oligomerization products are octene dimers having an alkylnaphthene structure and containing unsaturated hydrocarbons with tri- and tetra-substituted double bonds in amounts of 2.2–3.2%. The properties of the octene oligomers synthesized in the presence of zeolite Beta are similar to the characteristics of hydrogenated poly-α-olefins, the oligomerization of which was performed on AlCl3 complexes.  相似文献   

7.
Based on the mechanism analysis of the polychlorination of long chain n-alkanes by photo-initiation, a kinetic model was developed. The model parameters were obtained by the method of non-linear fitting. The influences of luminous intensity and concentration of molecular chlorine on the rate of polychlorination are demonstrated by the model. If the luminous intensity is adequate, the polychlorination rate of n-alkane is only controlled by the flow rate of molecular chlorine in a wide range of temperature, and the changes of temperature and luminous intensity have less effect on the reaction rate. In addition, the predictions of chlorine content, of polychlorinated n-alkane calculated with the model agree very well with experimental results.  相似文献   

8.
Zircon (mesh size ≤ 44μm ) and carbon black (mesh size ≤30μm ) were used as the starting materials, weighed with re(zircon) : re(carbon black) of 100 : 20 and mixed fully. The specimens with the diameter of 20ram and length of 5ram were prepared by pressing at 100 MPa, then dried at 120℃ for 12h, put into a furnace with 1. 5L ·min^-1 argon gas and fired at 1450℃, 1500℃, 1550℃, 1600℃ and 1650℃ for 4h, respectively. The chemical composition, phase composition and microstructure of the specimens were studied by chemical analysis, X-ray diffraction and scanning electronic microscope, and the carbothermal reduction reaction process was discussed by thermodynamic analysis. The results showed that the ZrO2-SiC composite could be synthesized by carbothermal reduction reaction using zircon and carbon black as the starting materials in argon atmosphere. The composite with different composition was obtained by controlling the firing temperature and partial pressure of CO gas. The proper temperature to synthesize ZrO2-SiC composite was 1600℃ in this experiment.  相似文献   

9.
Sintering additivesto gelcasting Sialon‘SiC were decided by the optimizing experiments , The resuhs show that Sialon-SiC can be sintered under 1450℃ and sintering temperature dcreases by 100℃,when 2%~3% TiO2 or Guangxi clay is used as sintering additive.  相似文献   

10.
Deodorizer distillate is an important by-product obtained during deodorization in the edible oil industries. It is a complex mixture of many health beneficial constituents like phytosterols, tocopherols and squalene. In the present study a simple gas chromatographic method with mass spectrometry was used for the separation, detection and quantification of different components present in the deodorizer distillate in a very short analysis time of 18 min. A simple saponification procedure without derivatization was used for their analysis followed by GC–MS analysis. Phytosterols concentration (21.27–25.53%) was the most abundant in canola and palm distillate samples whereas, squalene and tocopherol were present in concentration ranges of 2.89–13.21% and 1.29–5.81%, respectively. The present study revealed that the unsaponifiable fraction of deodorizer distillate could be used in cosmetic preparations due to its appreciable amount of bioactive constituents.  相似文献   

11.
A heterostructure of Ag/ZnO powder was prepared by a reduction of Ag(NH3) 2 + ions in a basic solution or Tollen’s reagent. From this method, the existence of a metallic Ag coating on the ZnO surface was confirmed by transmission electron microscope and x-ray photoelectron spectroscopy. The photocatalytic activity of the Ag/ZnO powders was investigated by analyzing the degradation of an aqueous methylene blue solution under a blacklight irradiation. Furthermore, the parameters, including Ag content, catalyst loading, initial dye concentration and pH, were also studied. After the methylene blue solution was irradiated for 30min under a blacklight illumination, total mineralization was not observed as the presence of some carbon compound species was indicated in a mass spectrum. Furthermore, the toxicity of the treated methylene blue solution produced by the Ag/ZnO powders was also investigated by a test for the inhibition of the growth of Chlorella vulgaris.  相似文献   

12.
13.
In this work, phosphotungstic acid (PTA) as a novel initiator was reported for the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL). It was found that PTA was an efficient initiator. ROP of ε-CL can be readily initiated by PTA at room temperature and form poly(ε-caprolactone) with narrow molecular weight distribution. Polymerization mechanism study indicates that the polymerization proceeds via acyl-oxygen bond cleavage.  相似文献   

14.
Reinforcement of EPDM by in- situ prepared metal salts of methacrylic acid   总被引:1,自引:0,他引:1  
利用中和反应在三元乙丙橡胶基体中原位生成甲基丙烯酸的各类金属盐,锌盐增强硫化胶的增强效果最好。在等摩尔的ZnO/MAA反应的胶料中添加过量ZnO显著提高了硫化胶的强度。广角X射线衍射证明了ZnO/MAA在EPDM中的原位反应。  相似文献   

15.
π-Conjugated organoboron polymers were prepared by haloboration-phenylboration polymerization beween diyne monomers and bromodiphenylborane. The polymerization was carried out by adding a slightly excess amount of bromodiphenylborane to a tetrachloroethane solution of diynes at room temperature under nitrogen and stirring the reaction mixture for 4 hours at 100°C. The obtained polymers were soluble in common organic solvents such as THF and chloroform. Their molecular weights were estimated to be several thousands by gel permeation chromatographic analysis. In UV-vis absorption spectra, bathochromic shift of λmax and absorption edge in comparison with the corresponding monomers were observed, which indicates the π-conjugation via vacant p-orbital of boron atom.  相似文献   

16.
Ectropis obliqua Prout is one of the most severe defoliator insects of tea plants. Sex pheromones method has been widely used for monitoring and controlling the insect pest of E. obliqua Prout due to their relative safety, low cost, and environmental friendliness. However, conventional preparing sex pheromones of E. obliqua Prout has been criticized by the costly and/or low efficiency procedure. Herein, we report a series of Fe-based metal–organic frameworks (MOFs) as efficient heterogeneous catalysts for the site-selective epoxidation of 3Z,6Z,9Z-octadecatriene to its monoepoxides. Particularly, MIL-100(Fe) combined with polyoxometalate (POM) as cocatalyst appears as the best catalyst for the oxidation of 3Z,6Z,9Z-octadecatriene to a high site selectivity to the corresponding 6,7-epoxide with good yields. 3Z,6Z,9Z-octadecatriene and its corresponding 6,7-epoxide are the primary sex pheromone components of the E. obliqua Prout. Significantly, the field bioassay experiments showed that the mixed products were highly effective in attracting E. obliqua Prout male moths. This work provides a general method to fast and clean synthesis of sex pheromones and opens new avenues for the application of Fe-based MOFs in the pest control with environmental friendliness.  相似文献   

17.
Based on a previous investigation, a simulation model was used for optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distil ation. An experimental setup was established to verify the simulated results. The effects of various operating variables, such as ethanol feed location, acetic acid feed location, feed stage of reaction mixture of acetic acid and n-butanol, reflux ratio of ethyl acetate reactive distillation column, and distil-late to feed ratio of n-butyl acetate column, on the ethanol/n-butanol conversions, ethyl acetate/n-butyl acetate purity, and energy consumption were investigated. The optimal results in the simulation study are as follows:ethanol feed location, 15th stage;acetic acid feed location, eighth stage;feed location of reaction mixture of acetic acid and n-butanol, eighth stage;reflux ratio of ethyl acetate reactive distillation column, 2.0;and distillate to feed ratio of n-butyl acetate, 0.6.  相似文献   

18.
The specific signatures of α-Al2O3 powders by a combination of X-ray diffraction (Rietveld analysis), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermal analysis (TG-DTA) and cathodoluminescence (CL) were investigated. Thus, α-alumina was prepared by calcination of boehmite or gibbsite at 1573 K for 24 h. The size of α-alumina crystallites obtained using boehmite precursor was smaller than that obtained using gibbsite precursor. The difference in oxygen vacancies (F+-centers) amount between α-Al2O3 powder obtained by calcination of gibbsite and boehmite was confirmed by CL spectra. Furthermore, the Ti3+ emission at 1.71 eV is absent in α-Al2O3 powder obtained by calcination of gibbsite. CL has been demonstrated as a possible method for differentiation between the various α-alumina powders.  相似文献   

19.
The polysilsesquioxane having amino and phenyl groups (APSQ) was prepared from the corresponding trimethoxysilanes by co-condensation under basic conditions. The amino group on APSQ was utilized as an initiator for graft polymerization of ?-caprolactone (CL). The ring-opening polymerization of CL, in the presence of a catalytic amount of the base prepared from triazabicyclodecene, proceeded effectively to afford the polysilsesquioxane having poly(CL) as the graft chains (GrPSQ). In the grafting, no formation of cross-linked product was observed. The grafted poly(CL) component in GrPSQ showed improved durability for heat as an advantage of the hybrid polymer containing polysiloxane structure.  相似文献   

20.
Equilibrium shapes of sessile liquid drops over horizontal substrates are modeled using smoothed particle hydrodynamics (SPH). The model can predict the variations of shape and contact angle of drops as a function of drop volume. In the model, a scheme of repositioning the particle at the triple line has been incorporated to attain the in situ contact angle. The simulations show a reasonable match with available analytical results. However, some mismatch of the drop shape near the three-phase contact line is observed. To improve the predictability, combined diffused interface smoothed particle hydrodynamics model (Das and Das, 2009b) is employed. The developed hybrid simulations improve the prediction. Estimated drop shapes and contact angle agree with experimental data reasonably well over a wide range of fluid properties and drop volume. The technique establishes the suitability of a particle-based hydrodynamic simulation for the modeling of complex interfaces and three-phase contact lines.  相似文献   

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