Advanced Materials Research Vol. 1035

Abstract: A novel peak diffusing measurement method is reported. In this method, a pulsed Gaussian heat source is focused on the material’s surface, and a thermal camera is utilized for detecting the temperature evolution. Specially, the peak temperature time t_max at different distance from the heat source center is extracted using the Singular Spectrum Analysis (SSA). Thermal diffusivity is then calculated by fitting multiple sets of extracted t_max into the derived regression equation. The advantage of this method is that it does not require the high precision time synchronization between the excitation source and detector. Also, the calculation process is very simple, which achieves an efficient in situ measurement of the thermal diffusivity. The measured radial thermal diffusivity of samples prepared from Ti and Ni is in good agreement with the reference data with a 1.8% and a 3.9% error bound.

Abstract: In this contribution, a simple and sensitive extraction-cleanup method which was termed MAE-μ-SPE, was developed for the analysis of pharmaceutical and personal care products (PPCPs) in environmental water samples. The PPCPs included bisphenol A (BPA), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP), tetracycline (TC), deoxytetracycline (DC), oxytetracycline (OTC) and chloroteracycline (CTC). In this method, the PPCPs in the samples were extracted by microwave-assisted extraction (MAE) following adsorbed by copper (II) isonicotinate in micro-solid phase extraction (μ-SPE) device. The PPCPs were determined by high performance liquid chromatography with ultra-violet detector (HPLC-UV). The procedure of the MAE-μ-SPE was optimized in extraction temperature, extraction time, desorption time and desorption solvent. Analytical performances, such as limits of detection (in the range of 2.0-8.5 μg/L), quantification (in the range of 6.6-28.0 μg/L), and repeatability of the over-all procedure (less than 13%) were established. DEP, DBP, DEHP and TC studied in water samples were ranged from 18.2-68.8 μg L^-1, while BPA, OTC, CTC and DC were found all below the detection limit in these samples.

Abstract: The complex nonlinear problem exists between the factors which influence the strength of hybrid fiber reinforced concrete. The nonlinear relationship between input variables as the factors and output variables as the strength can be obtained artificial neural network which have the feature of self-adapting, self-studying and nonlinear mapping. RBF and BP neural network models are established in MATLAB in this paper based on experimental values. Compressive strength and flexural strength of hybrid fiber reinforced concrete are predicted respectively and comparing with the measured values, predicted values are analyzed. The results show that the predicted values based on RBF tally with the experimental values, and the strength prediction ability of RBF is higher than BP neural network. The needs of engineering can be meet by this method with accurate prediction ability, a new method for the study of hybrid fiber reinforced concrete strength is provided.

Abstract: Because of their widely application of tantalum, niobium and lithium in industry, the occurrence modes of tantalum-niobium tailing mine in Yichun city was investigated by SEM, XRD, XRF measurement. Some interesting results are obtained, which is useful for the next flotation process and for the comprehensive utilization of lepidolite resources in Jiangxi province.

Abstract: Yichunhas the largest rare-metal reserves in China, the explored reserve of lepidolite accounts for 31% in China and 12% in the world, it reserves of Rb and Cs are also the largest in China. The mining process of tantalum-niobium in Yichun and the technical reconstruction for the tantalum-niobium tailing mine is investigated.

Abstract: Novel preservation of longans treated by edible coating was researched in a double-blind test at room temperature. The 1/10, 1/15 dilutions of No.1 and No.2 compound preservative solutions respectively were used, and their preservative effect on longan was evaluated by sensory analysis. The results showed that the compound preservative solutions could keep the quality of longans effectively. The concentration of the preservative solutions was not the key factor for improving their fresh-keeping ability in the experimental range. The optimum formula of the preservative solution was No.1 compound preservative solution diluted in the ratio of 1:10.

Abstract: The split, fall, collapse and severe diapirism of tube body happened on one of the tubing used in the gas well of high pressure and high production in the process of the trial extraction. This paper aims to explore the reason of its occurrence through the research of the macroscopic analysis, mechanical and chemical property test and microscopic metallographic test study. The result of the research shows that the multiphase flow of gas, liquid and solid in the tubing may produced an instantaneous negative pressure and increased the possibility of the tubing being collapsed in the process of gas testing and production.Then it resulted in clogging, severe ablation, thinning wall and piercing in tube and finally the tube broke because of the low tensile strength.

Abstract: Novel liquid composites were successfully prepared by blending copolymer (PEG/PHS) and carboxymethyl cellulose (CMC) in this work. PEG/PHS was achieved by introducing polyethylene glycol (PEG) into the main chain of poly hexanediol succinic (PHS). The results showed that the structure characterization of PEG/PHS was displayed in ¹H NMR spectrum. The interaction existed between PEG/PHS and CMC which was validated in FT-IR and SEM. This conjecture was simulated by molecular dynamics under the software YASARA. Because of the existence of interfacial interaction, composites films kept good thermal performance and the flexibility of composite films was greatly improved.

Abstract: Aerospace applications of composites involve components that are relatively thin plate or shell like structures, thus requiring the consideration of buckling as one of the many possible failure modes. To study the effect of the resin volume fraction on stability of composites, a finite element method based on micromechanics and classical lamination theory has been established to compute buckling loads of simply supported symmetric laminated composite plates subjected to the load of in-plane axial compress and shear load, respectively. The analysis procedure includes a Micromechanical finite element analysis that predicts the elastic modulus of lamina and a finite element linear buckling analysis that predicts buckling load of the composite plates. Three kinds of resin volume fraction that are equal to 44 percent, 47 percent, and 50 percent respectively are considered. The results show that the resin volume fraction has obvious influence on the stability of composite plate. The plate exhibits a relatively large increase in buckling load, about 12 percent, when the resin volume fraction increases by 3 percent. It is finds that the bending stiffness that has an obvious influence on the stability is an incremental function of elastic modulus and cubic thickness. The elastic modulus will be decreased slightly with the increase of resin volume fraction. However, the thickness of the plates is proportional to resin volume fraction.

Abstract: 316L stainless steel foams (SSFs) are fabricated successfully by polymeric sponge impregnation technology. The effects of mass fractions of PVA and powder on LOAD in impregnated sponge samples are investigated, and the effects of sintering temperature on apparent density, open porosity and bending strength of SSFs samples are also discussed. The experimental results show that the impregnated sponge samples may hold excellent 3D open-cell network structure and uniform muscles when the mass fractions of PVA and powder in slurry are kept in 9-13 % and 52-75% respectively; with rising the sintering temperature, the apparent density and bending strength of SSFs gradually increases, the open porosity reduces. After the temperature exceeds 1260°C, the bending strength reduces oppositely. A stainless steel foam sample with open porosity of 81.4% and bending strength of about 56.8 Mpa can be obtained after sintering at 1260 °Cfor 30min.