Surface modification of bioactive glass nanoparticles and the mechanical and biological properties of poly(L-lactide) composites

Novel bioactive glass (13G) nanoparticles/poly(L-lactide) (PLLA) composites were prepared as promising bone-repairing materials. The BG nanoparticles (Si:P:Ca = 29:13:58 weight ratio) of about 40 run diameter were prepared via the sol-gel method. In order to improve the phase compatibility between the polymer and the inorganic phase, PLLA (M-n = 9700 Da) was linked to the surface of the BG particles by diisocyanate. The grafting ratio of PLLA was in the vicinity of 20 wt.%. The grafting modification could improve the tensile strength, tensile modulus and impact energy of the composites by increasing the phase compatibility.

Novel acidic porous clay heterostructure with highly ordered organic-inorganic hybrid structure: one-pot synthesis of mesoporous organosilica in the galleries of clay

A new class of organic-inorganic hybrid porous clay heterostructures (HPCHs) have been prepared through the surfactant-directed assembly of organosilica in the galleries of montmorillonite. The reaction involved hydrolysis and condensation of phenyltriethoxysilane and tetraethoxysilane in the presence of intragallery surfactant templates (dodecylame and cetyltrimethylammonium ion). The surfactant templates were removed from the pores by solvent-extraction. The products were characterized by X-ray diffraction (XRD), N-2 adsorption, solid-state Si-29 and C-13 NMR, and FTIR. XRD patterns indicated a regular interstratification of the clay layers for HPCHs. Depending on loading of phenyl groups, HPCHs had BET surface areas of 390-771 m(2) g(-1), pore volumes of 0.3-0.59 cm(3) g(-1), and the framework pore sizes in the supermicropore to small mesopore range (1.2-2.6 nm). HPCHs were hydrophobic and acidic.

A novel way to synthesize high regular and periodic organic mesoporous silicas

Organic mesoporous silicas (OMSs) were synthesized in the presence of urea via one-pot synthesis method, in which tetraethyl orthosilicate (TEOS) and 3-aminopropyltriethoxysilica (APTES) were used as the silica resources, non-ionic surfactant was used as the template. XRD results showed that the average periodic mesopore sizes of OMSs in the presence of urea were larger than those in the absence of urea. It was also found that the pore sizes of the products in the presence of urea distributed more narrowly than those in the absence of urea, and the contents of organosiloxane incorporated into OMSs, the pore wall thicknesses, the pore volumes and the surface areas of the products all increased with the use of urea. This shows a novel way to synthesize high regular and periodic organic mesoporous silicas.

微孔-介孔复合SiO2-Al2O3分子筛的水热合成研究

中国科学院山西煤炭化学研究所

三塘湖盆地牛圈湖区储层特征研究—以齐古组、头屯河组为例

In view of few researches into pore textures and anisotropy characteristics of Qiguzu-toutunhezu reservoir in Niuquanhu block in Santanghu Basin, in order to enhance the hydrocarbon recovery of the region of interest and improve the reservoir development effect, with the employment of the experiments like cast thin slice, scanning electron microscope, conventional high pressure mercury penetration, constant speed mercury penetration and nuclear magnetic resonance, the thesis makes a thorough research into pore texture characteristics and anisotropy characteristics of the sandstone reservoir. The research shows that the microscopic pore textures are complicated, the anisotropy is high and waterflood development water/oil displacement efficiency is low, which are mainly caused by the high microscopic anisotropy of the reservoir. Specially, the research shows that Qiguzu-toutunhezu reservoir belongs to braided delta front intrafacies, the intergranular pore is the main type of pores, which take up 65.50 percent of total pores, intergranular dissolved pores, feldspar dissolved pores and lithic dissolved pores are on the second place, and there are few carbonate dissolved pores. The reservoir belongs to mesopore-fine throat and mesopore-medium throat. The pore distribution of the sandstone reservoir is comparatively centralized. The reservoir inhomogeneity is mainly caused by the throat inhomogeneity. Diagenesis mainly includes compaction, cementation, metasomatism and dissolution. Compared with compaction， cementation exerts more direct impact on the decline of the porosity of the sandstone reservoir ( pore loss factor is 63.75 percent in the cementing process). Based on the classification of diagenetic stages, the reservoir diagenesis is on the stage of the late period of early diagenetic stage to early period of late diagenetic stage. The study area of the small sandstone reservoir layer of the anisotropy of the relatively strong; plane, the anisotropy of the relatively weak. microscopic anisotropy of its relatively strong.

Templateless synthesis of catalysts with narrow mesoporous distribution

In this study, amorphous silica-alumina nanomaterials with narrow mesoporous distribution can be obtained by two novel sol-gel processes, without the use of any templates. The results of our experiments show that the preparation method has a great influence on the precursor sol structure as well as the specific surface area and mesopore volume of the final product, but has no effect on the pore size distribution.

Sol-gel derived oxides and mixed oxides catalysts with narrow mesoporous distribution

A novel sol-gel process for preparing oxides and mixed oxides sols from precipitation and peptization process is reported in this article. Inorganic salts are used as raw materials in this study. It is found that the amount of acid has great influence on the stability and particle diameter distribution of the precursor sols. Ultrasonic treatment is used to prepare alumina sol at room temperature. The result of Al-27 NMR shows that there exist Al-13(7+) species in the sol. By controlling the sol particles with narrow particle diameter distribution, alumina, titania and silica-alumina (SA) materials with narrow mesoporous distribution are formed by regular packing of sol particles during gelation without using any templates. The results also show that the structure and particle diameter distribution of precursor sol determine the final materials' texture.