Papers by Keyword: Chroma

Abstract: A novel perovskite-structured black pigment was synthesized for the fabrication of black aesthetic zirconia ceramics. The influences of pigment content and sintering parameters on the density, mechanical strength and chroma of final black zirconia ceramics were investigated. The results showed that the doping content of black agent should be not less than 2.5 wt.% to yield sufficient blackness. The optimal sintering temperatures for the fabrication of black zirconia were 1400~1450 °C. Higher sintering temperatures would result in the decomposing black agent, consequently decreasing the density, chroma and mechanical strength of final products. The black zirconia ceramics with 2.5 wt.% doping agent prepared at 1450 °C yielded the final density of 6.02 g/cm³ and bending strength of 960±30 MPa. The L, a and b values of the black zirconia were 48, -0.12 and 0.25, respectively.

Abstract: The effect of a novel amphoteric polymeric flocculant, p (DMC/NVP/FA), was investigated in processing dyeing wastewater. The optimum for flocculant dosage was 55mg/L, and one for pH was 5. Under the optimum conditions, the intrinsic viscosity of flocculant and the removal rates of COD_cr and chroma reached the top (274.425dL/g, 80.1%, 92.6% ) . Analysis dyeing wastewater flocs SEM by calculating the D_f (a symbol stands for fractal dimension) values of fractal dimension with Non-Linear fractional theory. The results of the theorical computationare coordinated with the text.

Abstract: To meet the requirement of ceramic pigment for ink jet printing, CoAl₂O₄ pigment was prepared by nitrate-glycine method. The effect of nitrate/glycine ratio, calcination temperature and organic sacrificial agent on the particle size and chroma of the blue pigment were considered. The results show that the particle size of the pigment increases with the increase of glycine in the ratio and the decrease of the calcination temperature. However, the increase of the calcination temperature results in the broadening of the particle size distribution of the pigment. The addition of the organic sacrificial agent contributes to decrease the particle size of the pigment, which is about 2.0 μm. The chroma of the pigment is L*=47.62、a*=9.49、b*=-51.41. The blue pigment can be used in ink jet printing.

Abstract: By use of iron-carbon micro-electrolysis-UASB-SBR continuous process, treatment of an actual alkali dyeing wastewater (pH 11.50~13.50) taken from a certain factory in Xian-Yang was studied. The results indicated that: (1) When the influent COD is 1000~1600 mg·L^-1, chroma 250 times, firstly effluent COD reduced to 400~800 mg·L^-1 and chroma 40 times by iron-carbon micro-electrolysis process, secondly effluent COD dropped to 250~500 mg·L^-1 by UASB process, finally effluent COD dropped to 70~98 mg·L^-1 by a SBR with loading PVA micro-gel beads, which meet the direct emission limits of water pollutants for dyeing and finishing of textile industry (GB 4287-2012); (2) Effective combination process of iron-carbon micro-electrolysis with UASB-SBR can be obtained through HRT optimization of micro-electrolysis reaction (HRT=10), that not only meet the requirement influent pH of anaerobic reactor, but also greatly reduce the cost of alkaline in practical application of iron carbon micro-electrolysis.

Abstract: The laboratory-made dicyandiamide formaldehyde polymer is used to study the effect of the flocculation treatment of simulated wastewater of You Li Su-hong EB. And the influencing factors mainly include flocculant dosage, pH and temperature. The experimental results show that when the dicyandiamide formaldehyde flocculant dosage is 8mL / L and pH is acidic or neutral, COD and color removal rate are the highest that have reached more than 70%. Besides, temperature has little effect on the flocculation treatment, and room temperature is enough to make the treatment effect good. Finally compared with the commonly used flocculant PAC, dicyandiamide formaldehyde polymer treatment effect is better with less addition.

Abstract: Landfill Leachate is a kind of organic wastewater with high concentration and non-biochemical character, and Catalytic Wet Air Oxidation (CWAO) is suitable for this kind of wastewater treatment. In this study, Landfill leachate was treated with Catalytic Wet Air Oxidation (CWAO) method. The monitoring indicators consist of COD_Cr, absorbance, pH and chroma. The results show that: COD_Cr removal rate and decolorization rate of landfill leachate reduce with the reduction of the influent pH, the increment of water concentration and the extension of the reaction time; Under the optimized operating conditions: the influent pH of 8.10, the influent COD_Cr of 16611 mg/L, the reaction time of 90 min, the COD_Cr removal rate and decolorization rate of landfill leachate reach 56.8% and 83.7%, respectively. The effluent pH is 8.33 and chroma is 1600 times.

Abstract: Continuous treating process by iron-carbon micro-electrolytic technology treating actual dyeing wastewater was studied, performance of the micro-electrolysis reactor (MER) assembled homemade iron-carbon micro-electrolysis materials (MEM) and the process of alkaline addition, the properties of iron mud (flocculation precipitation produced from alkaline addition) were also investigated. The results shows that:(1) COD removal rate of MER was stable at around 60%, and the chroma could reached less than 40 times at stable stage of 60 days operation; (2) According to 30 days of continuous operation test, 7.6 kg of iron mud was produced when one ton wastewater was treated in this system; it was also found that iron mud can be recycled as raw materials for the synthesis of MEM by EDS analysis; (3)Effluent reflux (reflux ratio 1~1.5) could effectively reduce the dosage of alkali in practical process.

Abstract: 48 yellowish green peridots examined to test the color parameter under the neutral backgrounds whose lightness values are 10, 20, 30, 40, 50, 60, 70 and 80 by Color i5 tester, combing with the color parameter of peridots themselves, such as lightness values L*∈(50,60), chroma values C*∈(27,45), make the influence of different backgrounds on peridots’color appearence clear.With the help of two-factor analysis method, get that the F index of Row factor(standing for the lightness of peridots themselves): 16.61 which is greater than the its Fcrit index:1.40, and the F index of Column factor(standing for the lightness of backgrounds): 193.99 which is much greater than the Fcrit index, either, thus it shows that the peridots’color appearance is not only resulted by their onw lightness, but also by the backgrounds’. What is more, the influence of backgrounds is more significant; and comparing all samples’ chroma index fit line under different backgroud, find out peridot’s chroma index turning to be greater when the backgrounds’lightness increasing, and the influences are obvious during the samples with high chroma indexes. It is concluded that, for the peridots with medium lightness,the neutral backgrounds impact more on their color appearence than their own lightness do, and with the increase of backgrounds’lightness, peridots’lightness and chroma indexes will be higher.

Abstract: The main objective of designing skin color model is to determine whether the pixel is skin color pixels and generate the skin color mask images. The paper discusses the choise of color space and skin color model designing in skin color detection system, analysis the problems often needed to solve in it and put forward an improved skin color detection algorithm model based on ellipse boundary. The skin color detection experiment is completed. The result of experiment shows the skin color detection algorithm model is good.

Abstract: The chroma in tannery effluent was treated by prepared flocculant at different conditions. The results showed that the suitable reaction conditions were attained at a normal temperature, pH of 8, flocculant of 0.2 g/L when the shaking speed of 150 r/min and the reaction time was 15 min. Through testing the saccharide and protein in the flocculant, it was found that the flocculant contained saccharide and protein. These may contribute to the application of the flocculant to chroma removal in tannery effluent.