Advanced Materials Research Vol. 772

Abstract: 1-methyl-3-butyl Imidazole tetrafluoroborate is prepared by BMIC and NaBF₄ in the acetone. Scanning ionic liquid in 200~400nm wavelength range, get UV-spectrum curve. The ionic liquid used in the experiment has obvious absorption in 200~400nm wavelength range, and the maximum absorption wavelength determined by ultraviolet spectrometry method is 221nm. Linear regression equation is y=0.01128x+0.027. Correlation coefficient is 0.99957, indicating there is high related degree between the solution concentration and the absorbance value. The linear range of BMIBF₄ ionic liquid in the water is 1-75 mg/L. Take samples randomly and have a repeated determination 5 times, the precision is RSD=0.29%, the recovery rate is between 99.0%~102.3%.

Abstract: In this paper, collagen modified polylactide (CPLA) was synthesized by means of graft modification, and its structure was confirmed by FTIR and FITC-labeled fluorescence spectra. The performance of CPLA was characterized with hydrophilicity test and degradability test. The results showed that collagen had successfully grafted on the polylactide (PLA) and the graft ratio of collagen on CPLA was about 5%. The water absorotion of CPLA was significantly higher than PLA and its hydrophilicity was better than PLA. Moreover, there was no obvious acid-catalyzed self-accelerating degradation behavior in the degradation process of CPLA. The results suggested that CPLA showed a great potential as particles for drug delivery.

Abstract: The usability of artificial neural networks (ANN) for the estimation of the product distributions was investigated. The study was performed by following a model catalysis reaction, benzene alkylation with propylene on zeolite MCM-22. The effects of temperature, the ratio of benzene/propylene (B/P) and weight hourly space velocity (WHSV) on the product distributions were studied. Data obtained from different courses were used for training of the ANN and one set of data obtained from another courses was used for testing of the trained network. This network was designed as a Back-Propagation (BP) network with four neurons in the input layer, N neurons in the hidden layer and one neuron in the output layer. The network was trained till the mean square value between the targets and the outputs obtained was 1×10^-4. The product distributions for the isopropylbenzene, di-isopropylbenzene and tri-isopropylbenzene were estimated using the trained network. The regression coefficient of determination showed a good correlation between estimated and experimental data sets for both train and test data sets. There are high correlations between experimental and estimated time course curves and that was another proof of the high performance of ANN for estimation of the product distributions of alkylation reaction.

Abstract: Retinex theory combined the elements of images and visual.This paper improved the Retinex-based medical image enhancement method, It can get better brightness by using the neural network logarithmic The S-shaped LogSig transfer function instead of the original MSR logarithm function. Based on this, the paper presents a composite LRA (LogSig Retinex Algorithm) algorithm, and analysed the shortcomings of the original Retinex algorithm applied to the X-ray medical image analysis, described the advantage of the composite LRA algorithm is better than traditional Retinex algorithm on the X-ray medical image. Experimental results show that the improved Retinex algorithm can achieve not only low-contrast medical image enhancement, but also the dynamic range compression of the image, can significantly improve the information of the medical image of the dark area. It has practical significance for clinical diagnosis.

Abstract: To analysize the influence of singlet oxygen O₂(a¹Δ_g) and ozone O₃ on the hydrogen-air combustion system, a kinetic model must be defined. By simulating the ignition delay time, flame speed, flame temperature and the component changes of Starik model, GRI3.0 model, Konnov model and Mueller model using the software Chemkin4.1 and comparing the results with the experimental data, the Starik model is chosen as the basis of the study. Then singlet oxygen O₂(a¹Δ_g) and ozone O₃ is added in the basic model to form a new mechanism. The presence of singlet oxygen O₂(a¹Δ_g) and ozone O₃ is demonstrated to result in noticeable enhancement on flame propagation.

Abstract: onic liquid, 1-n-butyl-3-methylimidazolium chloride ([C₄mi Cl) was used to pretreat sugarcane bagasse (SCB), followed by regeneration of SCB by addition of deionized water. The regenerated SCB exhibited enhancement in enzymatic saccharification with an average 3.1-fold enhancement in yield of reducing sugar produced compared to untreated SCB in the kinetic study. The maximum yield of glucose and reducing sugar produced were 2.6% and 4.3% respectively for untreated SCB, whereas the maximum yield of glucose and reducing sugar produced were more significant with value of 7.2% and 16.6% respectively for IL-pretreated SCB. This paper suggested that the IL-pretreatment of SCB could be a useful pretreatment method to increase the yield of sugars produced in enzymatic saccharification.

Abstract: Using the Coconut chaff bran of grain size of 40 mesh as raw material, we carried out the subcritical hydrolysis experiment in 0-60 min, the reaction liquid ratio is 1:30. We establish its dynamic model by the experimental data fits subcritical hydrolysis reaction kinetic parameters. The study show that degradation temperature is the most significant factor which influences the degradation of the target product. The initial degradation activation energy of Coconut chaff Ea₁ is 68.35 KJ/mol and reducing sugar degradation activation energy Ea₂ is 83.27KJ/mol. And the pre-exponential factor K₁₀ is 3.16×10⁸h^-1 , K₂₀ is 5.56×10⁹h^-1_.

Abstract: Based on the vascular membrane stress model and the pseudo-elastic vessel model, the combination constitutive model with a layered structure in microvessel is presented in this paper. By using obtained constitutive equations of the current model, the circumferential stress of the membrane intimal (inner) layer and the three-dimensional stress distribution of the structural outer layer are analyzed. Under the initial blood pressure state, the vascular static stress changes with the inner stiffness increase are also discussed. The results show that with inner stiffness increasing, the stress of outer layer is less affected but the circumferential stress of the intimal layer is increased significantly, which may be one potential risk factor for the vascular injury. These analysis methods and its conclusions have some theoretical significance for studying the problems of arteriosclerosis and other diseases, and preventing the occurrence of related diseases.

Abstract: Since the palm fiber mattress which made of natural palm fiber and rubber is environmental friendly and has comfortable elasticity, this kind of mattress is very popular between consumers. This paper introduces the material, structure and morphology of the palm fiber layer through observation, analysis, experiment, and summarizes. The keys to improve related properties are screening of palm fiber, the density and moisture content of palm fiber layer, the content ratio of palm fiber and rubber and the artificial selection during stacking process.

Abstract: We have developed a novel high-strength antibacterial dental glass-ionomer cement (GIC). The functional quaternary ammonium salt (QAS)-constructed polymer (PQAS) was synthesized, characterized and formulated into the experimental high-strength cements. Compressive strength (CS) and S. mutans viability were used to evaluate the mechanical strength and antibacterial activity of the formed cements. Fuji II LC cement was used as control. The specimens were conditioned in distilled water at 37 °C for 24 h prior to testing. All the PQAS-containing cements showed a significant antibacterial activity, accompanying with an initial CS reduction. Increasing chain length, loading, grafting ratio significantly enhanced antibacterial activity but reduced the initial CS. Under the same substitute chain length, the cements containing QAS bromide were found to be more antibacterial than those containing QAS chloride although the CS values of the cements were not statistically different from each other, suggesting that we can use QAS bromide directly without converting bromide to chloride. The experimental cement showed less CS reduction and higher antibacterial activity than Fuji II LC. The long-term aging study suggests that the cements may have a long-lasting antibacterial function.