Advanced Materials Research Vols. 233-235

Abstract: This research aimed to study the use of curcumin as a natural dye for dyeing poly(lactic acid) and poly(ethylene terephthalate) fabrics. The study found that curcumin was dyeable on PLA and PET, providing a brilliant yellow color on the fabric. Curcumin could build up very well on PLA, while lower build up was on PET. At the same applied concentration, higher color yield was observed on the dyed PLA fabric. To achieve the same visual color yield, a significantly lower concentration of curcumin was required for PLA as compared with PET. The color shade of curcumin-dyed PLA differed from the PET analogue. A bathochromic shift of the K/S curve was found when the substrate was changed from PLA to PET. The influence of polymer media on the spectroscopic properties of curcumin could be elucidated by measuring absorbance properties of curcumin in ethyl acetate and methyl benzoate, being representatives of PLA and PET, respectively. At the same concentration, curcumin solution in ethyl acetate exhibited higher absorbance than that in methyl benzoate, corresponding to the deeper shade obtained when dyed on PLA as compared with PET. Bathochromic shift of absorbance curve was also observed when the solvent was changed from ethyl acetate to methyl benzoate.

Abstract: This research studied the potential and efficiency of tamarind kernel powder as a thickener for pigment printing on cotton fabric in comparison with the commercial synthetic thickener. Two kinds of tamarind seed were studied. Both of tamarind seeds contained about 30% based on dry weight of outer seed coating and 70% of dry weight of tamarind kernel powder. The approximate composition of tamarind kernel powder were 2.39 – 3.19% fat, 16.43 – 17.07% protein, 1.20 – 1.68% crude fiber and 3.42-3.74% moisture based on weight of tamarind kernel powders. Two different extraction techniques were studied viz., boiling in water and using microwave. Tamarind kernel powder extracted by microwave method was suited for use as a thickener rather than those obtained by boiling in water method. As the tamarind kernel powder from microwave method was easier dissolved and the printing paste was smoother than those from boiling in water. The optimum concentration of tamarind kernel powder for pigment printing on cotton was 5% tamarind kernel powder obtained from the seed in relatively round shape and smooth surface because the color yield and rubbing fastness was similar to the commercial synthetic thickener.

Abstract: In this paper, a new method is proposed for synthesis of property-based allocation networks. By analogy of concentration potential concepts proposed by Liu et al. (A heuristic design procedure for water-using networks with multiple contaminants, AIChE Journal, 2009; 55: 374-382) for the water-using networks, a new concept: the operator potential of sinks is introduced in this work. The operator potential of a sink is a measurement of the possibility of the sink to reuse the internal source streams. The sink with the lowest operator potential will be satisfied first. A literature example is studied to show the method proposed. The result shows that the method proposed in this work is very simple and the results obtained are consistent with those obtained in the literature.

Abstract: Optical reflectometry is applied as a tool for studying single and simultaneous adsorption of a carbohydrate, a nonionic surfactant, and a protein, For the nonionic surfactant poly(ethylene oxide) alkyl ether on a silica surface the adsorption process is fast and reversible, and the maximum adsorbed amount was 2.45 mg•m^-2. Also, the effect of pH on the adsorption of chitosan on silica, and its interaction with C₁₂EO₅ have been studied. The maximum adsorbed amount was obtained for pH ≥6.8 (0.80 mg•m^-2). Changes in surface functionality upon adsorbing C₁₂EO₅ on a chitosan layer and the protein, bovine serum albumin, are reported. The results are discussed in terms of adsorption kinetics, adsorbed mass plateau values, and reversibility of layer formation.

Abstract: Supercritical CO2 chelating-extraction was applied to remove heavy metal matter such as Pb, As and Hg from calcium lactate, and the effect of process parameters on removal efficiency were investigated including chelating agent, ethanol (as a modifier), temperature, extraction pressure and time. The results showed that the removal efficiency of trace heavy metals is obviously different from chelating agent, modifier and extraction time, thus the concentration of modifier and extraction pressure give little influence. The extraction process was optimized to get the condition of a temperature of 323.15K, a pressure of 20MPa, an extraction time of 90min, a supercritical CO2 fluid flow rate of 13l/h and 2% of the chelating agent mixtures combined with tetrabutyl bromide and sodium diethyldithiocarbamate (DDC). The maximum yield of Pb, As and Hg can reach 88.41%, 78.57% and 86.21%, respectively.

Abstract: Bastnaesite was activated at a temperature, and then the rare earths carbonate of the minerals was leached by HCl solution. When activation temperature was 400°C, activation time was 3h, HCl concentration was 3 mol•L^-1, leaching temperature was 90°C, liquid to solid was 20:1, the leaching ratio of rare earths carbonate and rare earths fluoride was 94.6% and 0.07% respectively. The results of XRD and SEM showed that bastnaesite was powdered and coarseness in activation process, which made the leaching of rare earths carbonate by HCl solution become easy. The main components of leaching slag were rare earths fluoride, calcium fluoride and barium sulfate.

Abstract: The article intends to introduce the authors’ experimental study on adsorption behaviour of chitosan and poly(acrylic acid) solution on silica by reflectometry. pH effect on adsorption-desorption of Chitosan and interaction with poly(acrylic acid) polyelectrolyte multilayer on silica has been studied. Builting multilayer formation on silica by 100ppm chitosan and 25ppm Poly(acrylic acid) solution with reflectometer. Effect of ionic strengths and molecular weight of chitosan have been discussed and we built 4 layers chitosan and 3 layers PAA and check BSA adsorption and stability. Atomic force microscopy measurement has been measured in the experiment. The results show adsorption kinetics, adsorbed mass plateau values, and reversibility of the layer formation which is typical for adsorption of strongly charged polyelectrolytes onto oppositely charged surfaces.

Abstract: New initiator of FFM6 is used to initiate the acrylic emulsion polymerization. The influences of concentration of FFM6 (c[I]) and polymerization temperature (T) on polymerization reaction rate (R_p) were discussed. R_p is proportional to (c[I])^1.4 which is different with classical emulsion polymerization whose R_p is proportion to (c[I])^0.4, that indicate polymerization mechanism of the reaction in the study is different with classical mechanism. The value of Ea, 56.4 kJ/mol, is lower than the value of general radical polymerization’s Ea (80.0-96.0 kJ/mol), which indicates the FFM6 can initiate acrylic emulsion polymerization at a lower temperature compared with the other kinds of initiator.

Abstract: Reactive distillation for tert-butyl alcohol dehydration to isobutene and water catalyzed with the cation exchange resin was carried out. A mathematical model for simulating the process was developed and verified by the experimental results. Then, the dynamic matrix control (DMC) method was put into the process to achieve an efficient control for high purity isobutene from the top of the reactive distillation column. The tracking test and anti-disturbance test of the control system were carried out, and the effect of DMC parameters such as predictive length, control weighting matrix, error weighting matrix and reference trajectory coefficient on the performances of DMC were discussed. The results show that the tuning of these parameters has significant effect to the performances of DMC.

Abstract: Zn (II)/SiMCM-41 and Fe (III)/SiMCM-41 showed high activity in disposal of CCl₄ into diphenyl carbonate (DPC) in presence of CO₂ at low temperature, due to Zn (II) and Fe (III) have zero Ligands Field Stabblized Energy (LFSE) and strong Lewis acid. Metal ions were immobilized onto the wall of Si-MCM-41, which keep metal cation leaching from catalyst during reaction