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《Arabian Journal of Chemistry》2020,13(1):134-145
This study proposed that hybrid scrap cast iron particles (SIP)-aerobic biodegradation technology could enhance the biodegradability of toxic wastewater. SIP cleaved the azo linkages of Direct Green1 dye to form benzidine, 4-aminophenol, aniline and 1,2,7-triamino-8-hydroxynapthalene-3,6-disulfonic acid. SIP-mediated dye reduction was effective at wide pH range; however, kinetic analysis revealed fastest pseudo-first order dye reduction rate at acidic pH 3 (kd = 0.549 min−1) followed by pH 9 (kd = 0.383 min−1) and pH 7 (kd = 0.318 min−1). The daughter aromatic amines produced were partially adsorbed onto the SIP surface and maximally at neutral pH. The adsorption process followed pseudo-second order adsorption kinetics and Langmuir isotherm. Benzidine was adsorbed more than 4-aminophenol and aniline. BOD5 of the SIP-treated effluent increased from 0.93 to 12 mg/L showing improved biodegradability. The daughter amines were rapidly mineralized in the aerobic bioreactor within 6 h. Cost-effective SIP pre-treatment could accelerate mineralization and detoxification of recalcitrant wastewater. 相似文献
13.
为对空中飞行目标实施合理有效的强激光干扰,需要综合考虑采用的干扰方式、干扰效果以及考虑光斑偏移对干扰效果的影响。以热传导理论为基础,建立了激光辐照下移动目标温度场模型,采用伽辽金法建立了有限元分析模型,采用了等效比热容的方法处理材料的相变过程;并以Ansys软件为仿真平台,对目标在高斯分布的强激光作用下的温度场和热应力进行了综合仿真分析。结果表明,光斑与目标辐照区域的相对偏移对目标表面温度影响较大,对目标纵深破坏效应相对较小,应力变化主要发生在激光辐照区域,应力最大处也会随热源的移动而变化。 相似文献
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柱前衍生—反相高效液相色谱法测定钢铁及合金中铌 总被引:1,自引:0,他引:1
建立了反相液相色谱法测定钢铁及合金中铌的分析方法。采用HNO3 HF H2 SO4 溶解样品 ,用酒石酸络合铌 ,以 2 (5 溴 2 吡啶偶氮 ) 5 二乙基氨基酚为柱前衍生试剂 ,在C18柱上用甲醇 水 (体积比为 5 6∶4 4 )为流动相 ,其中含 0 .0 1mol·L- 1pH为 3.5的HOAc NaOAc缓冲液。在60 0nm处测定了铌的配合物 ,方法检出限为 1.5 μg·g- 1。应用此法直接测定了合金铸铁和中低合金钢样品中铌 ,其加标回收率为 96.8%~ 10 3.2 % 相似文献
16.
稀土奥贝蠕铁制取工艺及其性能的研究 总被引:1,自引:0,他引:1
稀土奥贝蠕铁可用含稀土的蠕化剂及等温淬火工艺稳定地制取,藉助高温扫描电子显微镜,观察并研究了稀土蠕铁奥氏体化过程及稀土奥贝蠕铁随温度升高时组织的变化。用带有加热装置的万能材料试验等土奥贝蠕铁的各种性能进行了系统测定了如抗拉强度、延伸率、冲吉韧性、热膨胀系数及伸长百分率,结果表明,稀土奥贝蠕铁在室温和高温下均有良好的性能。 相似文献
17.
Substrate-free thin film of Nylon 13,13 has been prepared continuously by casting the polymer on a water surface from m-cresol solution. The uniform thickness of film is ca. 500 A, as measured with a Profilometer. Film morphology and properties have been characterized by transmission electronic microscopy (TEM), x-ray photoelectron spectroscopy, wide-angle x-ray scattering, differential scanning calorimetry and by contact angle measurements. Results show that there is no preferential accumulation of the amide group toward the water surface. A spherulite structure exists in this film with a crystallinity of 26% by DSC. Fibers were drawn from the films which had a tensile modulus of 5 GPa, stiffer than reported for this nylon as prepared by other means. Other members of the nylon series, such as Nylon 6, Nylon 12, have also been prepared in films by the same casting method under modified conditions. © 1995 John Wiley & Sons, Inc. 相似文献
18.
席位分配问题的数学模型 总被引:7,自引:4,他引:3
张建勋 《数学的实践与认识》2002,32(4):541-548
本文研究席位分配问题的求解方法及最优性评价标准 ,同时对现有方法的优缺点进行了分析 ,由此建立了充分体现所有成员平等的数学模型 ,并给出单位获得席位的检验数为 :bi=2 ni+ 1pi ,1 i m. 相似文献
19.
溶液成膜的温度对聚对苯二甲酸乙二酯结晶度的影响 总被引:1,自引:2,他引:1
<正> 用溶液成膜是制备聚合物薄膜的常用方法之一。但是溶液成膜的条件,如成膜温度,溶液浓度等对半结晶聚合物结晶度的影响研究报道较少。制备聚对苯二甲酸乙二酯(PET)非晶态薄膜通常使用熔融热压其后淬火的方法。由于PET在熔点附近易于降解,在薄膜中产生气泡,因而很难制备较大面积的均一厚度的薄膜,如在拉伸试验中所需 相似文献
20.
T. D. Dang S. J. Bai D. P. Heberer F. E. Arnold R. J. Spry 《Journal of Polymer Science.Polymer Physics》1993,31(13):1941-1950
Poly[(1,7-dihydrobenzo[1,2-d:4,5-d′] diimidazole-2,6-diyl)-2-(2-sulfo)-p-phenylene], a conjugated rigid-rod polymer, was derivatized with pendants of propane-sulfonated ionomers. The derivatized rigid-rod polymer was soluble in aprotic solvents as well as in water for isotropic solutions that were processed into isotropic films. Direct-current electrical conductivity σ of the films was measured using the four-probe technique. Room-temperature σ as high as 2.9 × 10?4S/cm was achieved on pristine isotropic films without using dopants. When the rigid-rod polymer concentration exceeded 25 wt %, the isotropic solution could be transformed into a liquid-crystalline solution that allowed deformations to be applied to produce anisotropic films. Significant increase in σ was obtained in a sheared film along both the parallel direction (∥) and the transverse direction (⊥) with a σ∥/σ⊥ = 5. Additionally, enhanced σ was realized in films heat-treated at about 100°C, in the derivatized polymer with higher molecular weight from dialysis, and in substituting the sulfonated ion Na+ by H+ in the pendants of the polymers. Constant-voltage measurements were applied to the polymers to monitor the σ stability for ascertaining the nature of the conductivity. No electronic contribution in σ was detected. Instead, a monotonically decreasing σ was consistently observed indicative of ionic conductivity. © 1993 John Wiley & Sons, Inc. 相似文献