Papers by Keyword: Preparation

Abstract: MFe₂O₄ (M=Mn, Co, Ni, Zn) Nanoparticles with diameters from 5nm to 30nm have been prepared through a hydrothermal method. In this system, ethanolamine was used as a basic source instead of NaOH. The as-prepared ferrites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, the magnetic properties of the obtained ferrites have been studied at room temperature, showing that the magentic properties of ferrites closely depended on the chemical composition of M²⁺.

Abstract: Bioglass is a good bioactive material and has been used in many medical fields, include drug delivery systems, non-load-bearing implants and bone cements. Sol-gel is a good method in the preparation of coating materials. It also can be used in the preparation of bioactive glass. In this paper, the principles and technical processes are introduced. The effects on characteristics of bioactive glasses of the factors such as H₂O dosage, ethanol dosage, gel temperature and activator are analyzed in detail. The research progress in preparation of sol-gel bioactive glasses is summarized. Finally the development foreground of sol-gel bioglass is also expected.

Abstract: Polymers and their composites are extensively used in commercial applications^[.Wearing is one of the forms which makes materials damage and failure, especially the materials by friction, impact, erosion like rocks, minerals etc, the wear caused huge losses. Therefore, high-strength wear-resistant engineering machinery rational use of materials is very important. So chose a method that simple, rapid, low cost, good effect to prevent and repair the parts wear is necessary. In recent years, there has been much interest in particle-reinforced polymers not only because to produce this kind of polymer is cheaper, but also they can be used as high quality engineering materials^[2]. In abrasive wear, the low stress also occupied a certain proportion of erosion^[. Current polymeric coatings, although corrosion resistant, do not satisfactorily resist wear, but these studies provided many ways to improve the erosion resistance of particle-reinforced polymers^[410].

Abstract: White carbon black (WCB) has important applications in many fields such as rubber production and bioengineering and it has become one of the most promising functional materials currently available on the market. This paper summarizes the preparation of domestic and overseas WCB and it introduces the application progress of WCB. The main problems regarding to the development and application of WCB and its future in China are also discussed.

Abstract: CIP particles first were coated with SiO₂ shell by the Stober process , then grafted the polyaniline by in-situ polymerization to prepare CIP/SiO₂/PANI core-shell composites. The CIP/SiO₂/PANI composites are composed the dielectric loss properties with the the magnetic loss properties, the morphologystructure and electromagnetic properties are characterized by SEMXRD and vector network analyzer, respectively. It is observed that SiO₂ and PANI are on the surface of CIP particles, XRD patterns further confirm that the CIP/SiO₂/PANI composites are synthesized successfully, and that interaction between components exist in the polymerization. In comparison with CIP, the complex permittivity of CIP/SiO₂/PANI composites have certain enhancement in 2-18GHz frequency range, but it has a very small impact on the complex permeability.

Abstract: In the EtOH/H₂O system, by means of heating reflux, V-type amylose-n-octanol complex which B-type microcrystalline starch made a combination with n-octanol was prepared. Through single factor experiments, the effects of the starch/n-octanol ratio, the ethanol concentration, cooling rate, holding temperature and holding time on the crystallinity of the V-type amylose-n-octanol complex have been investigated. The X-ray diffraction was used to analysis the crystal structure of complex. The synthetic conditions were as follows: the starch / n-octanol ratio 10:1, the ethanol concentration 35%, holding temperature 80°C, holding time 60min and cooling rate 5°C/h.V-type amylose-n-octanol complex was prepared under the condition, the crystal structure of complex was V type and the crystallinity reached 61.29%.

Abstract: A new molecularly imprinted polymer, which can be used for selective adsorption of chloramphenicol (CAP) from aqueous solutions, was successfully prepared by precipitation polymerization. The adsorption kinetic curve, adsorption isotherm and selective adsorption were measured by static method. The adsorption kinetics of MIPs for CAP reached the equilibrium at about 11 hours. The maximum adsorption capacity was 43.395 mmol/g, and the MIP has much higher adsorption quantity than NIP. Competitive adsorption studies showed that MIP offers the advantages of selectivity toward CAP compared with NIP in the presence other antibiotics. The results showed that the MIP possessed good specific adsorption capacity and selectivity for CAP.

Abstract: The flat transducer is composed of 1-3-2 piezoelectric composite and copper shell. The structure of transducer was determined according to design requirement and finite element analysis by ANSYS. The transducer was prepared by using a 25mm×25mm×4.8mm 1-3-2 composite chip, rigid foam backing, copper shell, polyurethane layer and acoaxial cable. The voltage response, source level, receiving voltage sensitivity and other performance were measured. The resonant frequency of transducer is 294kHz, the maximum transmitting voltage response is 159.6dB, 3dB bandwidth is 32kHz, source level is 208dB, receiving voltage sensitivity of the transducer is -203 ± 3dB in the frequency range of 50-250kHz frequency, the beam width of -3dB is 11º in the directivity.

Abstract: In order to improve the aqueous solutions viscosity and flocculation performance of cationic polyacrylamide, organic montmorillonite was added into polymerization system of polyacrylamide, the cationic polyacrylamide/dimethyl diallyl ammonium chloride/organic montmorillonite (CPAM/DMDAAC/MMT) nanocomposite was prepared by aqueous two-phase polymerization method. The influence of organic montmorillonite content, cationic monomer content, polyethylene glycol concentration, monomer concentration on the intrinsic viscosity of the CPAM/DMDAAC/MMT nanocomposite were discussed. The reaction conditions were optimized by orthogonal test. The chemical component and organic montmorillonite shape of the cationic CPAM/DMDAAC/MMT nanocomposite were analyzed by FTIR and XRD respectively. The results show that CPAM/DMDAAC/MMT nanocomposite with high aqueous solutions viscosity and beyond compare flocculation performance has been obtained by aqueous two-phase polymerization method. The CPAM/DMDAAC/MMT nanocomposite has been used very well as a flocculating agent.

Abstract: The magnetic polymer ICF targets are fabricated by depositing the Ni-P coats of on the surface of polystyrene microsphere by the electroless plating. The thickness and composition of the coat, and the surface roughness and magnetic property of the magnetic microsphere were examined and analyzed. The results indicated the examined indexes can basicallymeet the requirements of ICF targets.