Papers by Keyword: Modified

Abstract: This paper mainly describes the preparation of carbon nanotubes (CNTs) reinforced BMI/DBA composites, as well as the effects of CNTs contents on mechanical properties of BMI/DBA/CNTs nanocomposites. The results indicated that with the level of hydroxy-modified carbon nanotubes increased, the mechanical properties of the BMI/DBA/CNTs nanocomposites first increase then decrease. When the content of hydroxyl-modified carbon nanotubes was added to 0.75wt%, the mechanical properties of obtained nanocomposites reached the maximum. In addition, the hydroxyl-modified carbon nanotubes were found to be compatible with the polymer matrix effectively.

Abstract: The adsorption isothermal curve and thermodynamic adsorption of Cd²⁺ and Pb²⁺ on modified walnut shell from waster water were investigated using batch technique. The equilibrium adsorption data are fitted to Langmuir and Freundlich isotherm models and the model parameters are evaluated. The Langmuir isotherm model shows a better fit to adsorption data than the Freundlich isotherm model for the sorption of Cd²⁺ and Pb²⁺ on modified walnut shell. The maximum adsorption capacity of Cd²⁺ and Pb²⁺ by modified walnut shell is found to be 32.68 mg·g^-1 and 84.75 mg·g^-1 at 298K temperature, respectively. The adsorption processes of Cd²⁺ and Pb²⁺ has feasibility and spontaneous nature. Thermodynamic parameters depict the endothermic nature of sorption and the process is spontaneous and favorable.

Abstract: By blending the different ratio of the low viscosity of bisphenol A type epoxy resin with low viscosity ammonia catalytic phenolic resin, the performance of the resin systems were investigated by the gel time, viscosity, mechanical properties, heat resistance, flame retardance. In addition, DSC was used to detect the thermal property, and FT-IR monitored the reactive process of phenolic-epoxy resin. When the phenolic resin was mixed with 5% epoxy resin, the results were as follow: the gel time of 121 s at 150°C, viscosity of 7760 mPa·s at 30°C, flexural strength of 83.3 MPa, impact strength of 6.9 kJ/m², tensile strength of 20 MPa, heat deflection temperature of 148.5°C, oxygen index of 34.5% and the apparent cure activation energy of 94.2kJ/mol. The resin systems had higher service temperature, low viscosity, excellent mechanical properties and service characteristics, and it could meet the requirements of fast pultrusion process.

Abstract: The research studies the chemical modification of nano TiO₂ and its application in the preparation of binder of artificial marble with superior comprehensive performance. Considering the content of coupling agent(KH-570), modification time, hydrolysis temperature and condensation temperature as the main influence factors, through orthogonal test designs, the optimal modification parameters were obtained. The results show that the hydrophobic of modified nanoTiO₂ can reache 47%, and the artificial marble using polyster binder with modified nono TiO₂ as binder obtains compressive strength as high as about 100 MPa.

Abstract: Using butyl titanate as titanium source, lanthanum nitrate as a source of lanthanum, iron nitrate as an iron source, the titanium dioxide powder of lanthanum/iron single-doped and co-doped were synthesized by the sol-gel combustion method. The doped TiO₂ powders were characterized by X-ray powder diffraction (XRD) and infrared spectroscopy (IR), and the photocatalytic activity was studied with methyl blue, methylene chloride and formaldehyde as the source of pollution. The results show that we obtain TiO₂ anatase when the heat treatment temperature was 450 °C. When the amount of doped Lanthanum and iron were 0.5%, the grain size of the powder was significantly reduced and the degradation efficiency for organic pollutions was highly improved compared with pure TiO₂.

Abstract: in this paper ionic liquid 1-butyl-3-methylimizolium chloride was applied to modify the cotton fabric. The modified cotton fabric was characterized by FT-IR spectra, microscopy determination and the thermogravimetric analysis (DSC). The dyeing performances of the modified cotton fabric were determined. The results indicated that the dyeing performances of the modified cotton fabric were more than that of the unmodified cotton fabric.

Abstract: In order to develop a new substrate filler for wetland, Fly ash and soil was mixed and modified in different mass ratio, then, static adsorption and seepage purification experiments were carried out to choose four appropriate modified fillers for wetland model experiment. Experimental results showed that when the mass proportion of fly ash and soil was 3:7, the best treatment effect was achieved. While using this modified wetland for wastewater treatment, the removal rate of total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH₄-N) and COD was 57.52%, 97.58%, 93.78% and 89.53% respectively. The effluent concentration of TN could meet the priority standard (level B) of Discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002), while the effluent concentration of TP, NH₄-N and COD could meet the priority standard (level A).

Abstract: Abridging the chasm between the prevalently employed continuum methods (e.g. FEM) and discontinuum methods (e.g. DDA),the numerical manifold (NNM),which utilizes two covers, namely the mathematical cover and physical cover, has evinced various advantages in solving solid mechanical issues. The forth-order partial elliptic differential equation governing Kirchhoff plate bending makes it arduous to establish the -regular Lagrangian partition of unity ,nevertheless, this study renders a modified conforming ACM manifold element, irrespective of accreting its cover degrees, to resolve the fourth-order problems. In tandem with the forming of the finite element cover system that erected on rectangular meshes, a succession of numerical manifold formulas are derived on grounds of the minimum potential energy principle and the displacement boundary conditions are executed by penalty function methods. The numerical example elucidates that, compared with the orthodox ACM element, the proposed methods bespeak the accuracy and precipitating convergence of the NMM.

Abstract: Biodegradable polyurethane foam (PUF) was prepared by using tung oil and starch as the modifiers, they were mixed with polyether polyol and some other reaction auxiliary agents, and then reacted with toluene diisocyanate (TDI). The structure and thermal stability of products were analyzed based on SEM and TG, and the soil burial method was used to investigate the biodegradability of products. The results indicated that polyurethane foam modified by tung oil and starch has good thermal stability, good mechanical properties and good biodegradability. The degradation rate of PUF modified by 5: 2 of starch/ tung oil was 38% after 120 d.

Abstract: In order to prepare high reflectivity titanium dioxide, by sol - gel method after nano-titanium dioxide powder, which silane coupling agent KH-570 covering it and make its surface modification.When the reaction temperature is 40 °C, drop accelerated rate 1.5mL/min, calcination temperature about 600 °C, got titanium dioxide with relatively high reflectivity and particle size in around 65 nm.When the amount of the silane coupling agent is 0.5%, the pH of reaction system is 6.5, and the reaction time was 1.5h, the nano-modified titanium dioxide particles with high reflectance.