排序方式: 共有5条查询结果,搜索用时 0 毫秒
1
1.
Romário J. da Silv Lizeth Carolina Mojica-Sánchez Filipe D.S. Gorz Graciela C. Pedro Bruna G. Maciel Gabriela P. Ratkovski Hérica D. da Roch Kamila T.O. do Nascimento Juan C. Medina-Llamas Alicia E. Chávez-Guajardo José J. Alcaraz-Espinoz Celso P. de Melo 《环境科学学报(英文版)》2021,33(2):62-73
We report the preparation of poly(3,4-ethylene dioxythiophene) (PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange (MO) from aqueous media. This novel adsorbent material can be used to selectively remove MO on a wide pH range (3.0–10.0), with a maximum capacity of 143.8 mg/g at pH 3.0. When used in a recirculating filtration system, the maximum absorption capacity was reached in a shorter time (20 min) than that observed for batch mode experiments (360 min). Based on the analyses of the kinetics and adsorption isotherm data, one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is electrostatic. Besides, considering the estimated values for the Gibbs energy, and entropy and enthalpy changes, it was established that the adsorption process is spontaneous and occurs in an endothermic manner. The good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles, without significant loss of their characteristics. We suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems. 相似文献
2.
Jin Zhang Qiang Yang Xiaofei Song Hui Qiao Junhao Zhang 《International Journal of Green Energy》2017,14(12):1011-1019
Electrospun cellulose acetate (CA) nanofibrous mats incorporated with capric acid was studied to fabricate form-stable phase change materials (PCMs) for storing/retrieving thermal energy. Electrospun CA nanofibrous mats with different porous structures and specific surface areas were firstly prepared through regulating the volume ratio of mixture solvent of acetone/dichloromethane (DCM). Effects of different volume ratio of mixture solvent and mat thickness on the morphological structure, specific surface area, and absorption capacity of CA nanofibrous mats were systematically investigated. The results indicated that CA nanofibrous mats were highly porous on the surface; hence, they were capable of absorbing a large amount of capric acid. The maximum absorption capacity of CA mats via electrospinning with volume ratio of acetone/DCM being 5/5 was ~95.8 wt%, due to its higher specific surface area of ~17.1 m2/g. The specific surface area and capric acid absorption capacity of CA nanofibrous mats increased with the increases of mat thickness. As the thickness of nanofibrous mats increased from 10 to 85 μm, the corresponding specific surface area and capric acid absorption capacity of mats increased respectively from 7.2 to 29.0 m2/g and 92.1 to 98.5%. Morphological structures, as well as the properties of thermal energy storage and thermal insulation of the fabricated form-stable PCMs, were studied by scanning electron microscopy, differential scanning calorimetry, and measurement of freezing times, respectively. The results indicated that the resulting form-stable PCMs could well maintain their phase transition characteristics and demonstrated great thermal energy storage capability and temperature regulation ability. 相似文献
3.
太湖竺山湾藻华黑水团区沉积物中Fe、S、P的含量及其形态变化 总被引:20,自引:9,他引:11
对因藻华大量聚集死亡而造成水体呈强还原环境(DO=0.14 mg.L-1,Eh=-89.3 mV)的黑水团区中Fe-S-P的生物地球化学变化特征进行研究.结果表明,藻细胞残体的沉降使得黑水区沉积物表层有机质含量显著增加;因藻细胞残体的贡献,沉积物表层中Org-P含量急剧增加(比非黑水区多72 mg.kg-1);受较低Eh的影响,沉积物中与Fe结合的磷出现解析,使得黑水区沉积物中活性铁和PO43--P含量增加,黑水区中沉积物间隙水PO43--P要远高于非黑水团区,表明其有向上覆水释放的趋势;造成沉积物中Fe-P含量比非黑水区中的要低.在强还原条件下沉积物中铁的氧化物呈现出由结晶态向无定形态转化的趋势(Dithio-Fe比非黑水区高达30μmol.g-1),从而使得可供生物利用的活性铁含量增加,这为藻华再次发生提供了有利条件.黑水区表层沉积物中酸可挥发性硫化物(AVS)在初始阶段大量增加,但后期由于形成了H2S气体逸散到水体中其含量反而减少;表层沉积物硫化物含量也呈增加现象(比非黑水区表层沉积物中要高50μmol.g-1). 相似文献
4.
Gast n Azziz Mat as Gim nez H ctor Romero Patricia M. Valdespino-Castillo Luisa I. Falc n Lucas A. M. Ruberto Walter P. Mac Cormack Silvia Batista 《Frontiers of Environmental Science & Engineering》2019,13(3):44
5.
Nord L. Gale Bobby G. Wixson Michael G. Hardie J. Charles Jennett 《Journal of the American Water Resources Association》1973,9(4):673-688
The New Lead. Belt of southeastern Missouri has recently become the largest lead producing region of the world. The impact of this rapid development on the previously rural and undeveloped region of the Missouri Ozarks is the subject of a continuing interdisciplinary study. Since the industrial development began, there have been a number of nuisance biological blooms in several of the small streams receiving effluent from the mines and mills. The major constituents of the problem algal growths were identified and found to include: Cladophora, Oscillatoria, Mougeotia, Zygnema, Spirogyra, Cymbella, and a variety of other stalked and non-stalked diatoms. Secondary blooms of Sphaerotilus were observed to reach problem proportions in some streams, particularly in the autumn. Finely ground rock flour and mineral particles escaping from tailings dams were found to be trapped by the stream vegetation. Concentrations of lead, zinc, copper, and manganese in the algal and bacterial mats were found to be inversely related to distance downstream from the tailings dams. Consumer organisms, including crayfish, snails, aquatic insects, tadpoles, minnows and larger sunfish were analyzed to determine the extent of dissemination and concentration of the heavy metals through food chains. Preliminary results indicated insignificant concentrations of heavy metals in those consumer organisms studied, though in at least one problem stream the normal consumer organisms mentioned were markedly reduced in numbers. 相似文献
1