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排序方式: 共有691条查询结果,搜索用时 468 毫秒
681.
682.
C. V. Chaudhari K. A. Dubey N. K. Goel Y. K. Bhardwaj L. Varshney 《Polymer Bulletin》2012,69(7):779-793
An efficient and low-cost effluent adsorbent has been developed by grafting an ionizable monomer onto polyolefin surface and its efficacy was tested for dyes and metal ion uptake from aqueous medium. The grafted matrix was synthesized by optimizing various experimental parameters such as irradiation dose, dose rate, monomer concentration, inhibitor concentration, surfactant concentration, and backbone thickness. Grafting yield decreased with dose rate and thickness and increased with the concentration of methacrylic acid and inhibitor. Grafting kinetics studies indicated that grafting rate is comparatively much affected by dose rate that monomer concentration. Surface energy of the grafted surface was accessed from dynamic contact angle measurements. Uptake study of Basic Red 29, Methylene Blue showed high correlation with grafting yield and polar component of the surface energy; however, metal ion uptake was exceptionally high at ~25 grafting (%), highlighting anomalous behavior of MAA-g-LDPE with respect to surface energy and total ion uptake capacity. 相似文献
683.
684.
K. A. Dubey Y. K. Bhardwaj Lata Panicker C. V. Chaudhari Virendra Kumar N. K. Goel S. Sabharwal 《应用聚合物科学杂志》2008,110(6):3552-3559
The miscibility of polychloroprene rubber (CR) and ethylene–propylene–diene terpolymer rubber (EPDM) was studied over the entire composition range. Different blend compositions of CR and EPDM were prepared by initially mixing on a two‐roll mill and subsequently irradiating to different gamma radiation doses. The blends were characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, density measurement, hardness measurement, and solvent permeability analysis. The compatibility of the blends was studied by measuring the glass transition temperature and heat capacity change of the blends. The immiscibility of blends was reflected by the presence of two glass transition temperatures; however, partial miscible domains were observed due to inter diffusion of phases. Permeation data fitted best with the Maxwell's model and indicated that in CR‐EPDM blends, EPDM exists as continuous phase with CR as dispersed phase for lower CR weight fractions and phase inversion occurred in 40–60% CR region. It was observed that CR improved oil resistance of EPDM; however, the effect was prominent for blends of >20% CR content. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
685.
The influence of Al2O3 (8 wt.%) on sintering and crystallization features of glass powders based on magnesium silicate (MgSiO3) was experimentally determined. The investigated compositions were Y0.125Mg0.875Si0.875B0.125O3 and Y0.125Mg0.725Ba0.15Si0.875B0.125O3. For the experiments, glasses in bulk and frit forms were produced by melting in Pt-crucible at 1600 °C for 1.5 h. Glass-powder compacts were sintered at different temperatures between 900 °C and 1100 °C. The evolution of crystalline regime was determined by in situ recording of X-ray diffractograms of fine glass powders at elevated temperatures. The results and their discussion showed that addition of 8 wt.% Al2O3 in glass batches affected the thermal properties of the glasses and resulted in MgSiO3-based glass ceramics well sintered between 900 °C and 1100 °C. In the BaO-free MgSiO3 glass ceramics, clino- and orthoenstatite crystallize while the presence of BaO favours the formation of hexacelsian. 相似文献
686.
在对污水处理厂历史监测数据收集、整理和分析的基础上,利用GPS-X软件,建立并校正了污水处理厂工艺模型,同时探索了校正方法。研究结果表明,自养菌最大比生长速率作为污水特征参数,需通过拟合出水的NH3-N浓度变化进行校准。污泥浓度的拟合是一个非常重要的步骤,影响污泥浓度拟合的参数包括进水特征参数(VSS/TSS值、总COD中颗粒惰性组分的占比)、剩余污泥排放量、初沉污泥排放量。 相似文献
687.
Cotton fibres were dyed using various natural dyes alone and in combination to yield six basic shades: blue, yellow, red, black, green and fawn. These dyed fibres were then blended in various proportions along with undyed cotton fibres and spun on a rotor-spinning machine to produce 204 coloured yarns. The fastness properties of the six basic shades were determined. The L * a * b * and L * C * h values of the yarns having 50% dyed fibre and 50% undyed cotton fibre was also determined. The values were plotted to obtain the colour gamut of natural dyes on cotton yarns. 相似文献
688.
Xinyi Xu Rajan Saini Enver Koray Akdoğan John Stuart McCloy Ashutosh Goel 《Journal of the American Ceramic Society》2023,106(6):3375-3395
Owing to its good chemical and thermal durabilities at high temperatures, Monofrax K-3 refractory is widely used in nuclear waste vitrification as a lining material in melting vessels. However, the corrosion of K-3 refractory during the vitrification of nuclear waste is a serious problem because it affects the melter's safety, performance, and lifetime. Therefore, in the present study, we have focused on unearthing the impact of glass network formers, such as SiO2, B2O3, and Al2O3, in a model nuclear waste glass composition on the corrosion of Monofrax K-3 refractory. The corrosion tests have been performed per ASTM C621 at 1150°C for 5 days. The dimensional measurements on corroded K-3 refractory suggest that Al2O3 and SiO2 tend to reduce the refractory corrosion (neck loss), with the effect of Al2O3 being significant. A corroded region on the K-3 refractory at the melt–refractory interface is observed. The corrosion occurs via a coupling of the melt infiltration induced by a capillary effect and the dissolution of Al, Mg, and Fe components from K-3 into the melt through chemical reactions. A Cr-rich layer is retained on the glass contact surface of the corroded K-3 refractory. 相似文献
689.
Silicon - In this paper, Gallium Nitride (GaN) based Dielectric Engineered High-K GaN Schottky Nanowire Field Effect Transistor (DE-HK-GaN-SNWFET) is examined for enhancing analog performance for... 相似文献
690.
Singh Simerneet Jatana Nishtha Goel Vasu 《Universal Access in the Information Society》2023,22(1):121-131
Universal Access in the Information Society - Digital media has brought a revolution, making the world a global village. For people who are visually impaired and people with visual and hearing... 相似文献