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31.
以国内某焦化企业场地多环芳烃污染土壤为研究对象,研究了过硫酸钠作为氧化剂时,硫酸亚铁或次氯酸钠助剂的使用对修复效率的影响,同时通过对比阐述了硫酸亚铁及次氯酸钠在过硫酸钠氧化体系中的不同作用。结果表明:微量硫酸亚铁对过硫酸钠氧化土壤中多环芳烃起到催化作用,可显著提高多环芳烃去除效率;次氯酸钠可与过硫酸钠协同使用,达到共氧化的目的。 相似文献
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Han Sol Kang Jinseong Lee Suk Man Cho Tae Hyun Park Min Ju Kim Chanho Park Seung Won Lee Kang Lib Kim Du Yeol Ryu June Huh Edwin L. Thomas Cheolmin Park 《Advanced materials (Deerfield Beach, Fla.)》2017,29(29)
Structural colors (SCs) of photonic crystals (PCs) arise from selective constructive interference of incident light. Here, an ink‐jet printable and rewritable block copolymer (BCP) SC display is demonstrated, which can be quickly written and erased over 50 times with resolution nearly equivalent to that obtained with a commercial office ink‐jet printer. Moreover, the writing process employs an easily modified printer for position‐ and concentration‐controlled deposition of a single, colorless, water‐based ink containing a reversible crosslinking agent, ammonium persulfate. Deposition of the ink onto a self‐assembled BCP PC film comprising a 1D stack of alternating layers enables differential swelling of the written BCP film and produces a full‐colored SC display of characters and images. Furthermore, the information can be readily erased and the system can be reset by application of hydrogen bromide. Subsequently, new information can be rewritten, resulting in a chemically rewritable BCP SC display. 相似文献
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Cellulose Nanocrystals from Lignocellulosic Raw Materials,for Oxygen Barrier Coatings on Food Packaging Films
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Stefano Gazzotti Marco A. Ortenzi Giulio Piva Luciano Piergiovanni 《Packaging Technology and Science》2017,30(10):645-661
Cellulose nanocrystals (CNCs) are unique, renewable top‐down nano particles from which coatings with improved gas barrier properties and new functionalities can be prepared. In this paper, the potential for obtaining such high performing nanocrystals from low‐cost lignocellulosic by‐products or raw materials is proved by a comparison study on CNCs obtained both from cotton linters and kraft pulp, by means of the ammonium persulfate (APS) process. Morphological and chemical characterization of the nanocrystals obtained, as well as the main functional properties of the poly(ethylene terephthalate) coated films, showed quite similar characteristics and performances of CNCs obtained from pure cellulose raw material (cotton linters) and the nanoparticles produced from a potential discard of paper making processes (kraft pulp). In particular, the gas barrier properties of the coating produced with CNCs obtained from kraft pulp were very promising, providing oxygen and carbon dioxide permeability values hundreds of times lower than those of equal thickness in comparison with common barrier synthetic polymers, over a broad range of temperatures. The results obtained are relevant not only for the outstanding performances achieved, but also because they evoke a possible positive example of industrial symbiosis in the packaging field, merging together the requirements and needs of the paper and plastic industries and addressing the way towards a better management of waste and materials. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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K_2S_2O_8/Na_2S_2O_3引发剑麻纤维接枝的研究 总被引:2,自引:0,他引:2
采用K_2S_2O_8/Na_2S_2O_3氧化还原体系作为剑麻纤维接枝的引发剂,能够降低反应的温度,提高纤维素的接枝率和单体的转化率。文章讨论了过硫酸钾、硫代硫酸钠和反应温度对剑麻纤维接枝的影响。 相似文献
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ABSTRACTThe efficacies of UV photolysis, UV-activated persulfate (UV/PS), and combined UV/Fe2+-activated persulfate (UV/PS/Fe2+) systems for degrading of different organic micropollutants in ultrapure water and groundwater were examined and compared. The studied micropollutants belonging to the different classes involved an artificial sweetener acesulfame K (ACE), beta-lactam antibiotic amoxicillin (AMX), and endocrine disrupting compound 4-nonylphenol (NP). Among the studied systems, the UV/PS/Fe2+ process showed the highest performance both in degradation and in mineralization of ACE (UVA-induced systems; kapp = 0.126 1/min and 80.3% TOC removal) and AMX (UVC-induced systems; kapp = 1.383 1/min and 85.4% TOC removal), followed by the UV/PS process. In the case of NP trials, the application of UVC/PS systems was the most promising, and after careful adjustment of oxidant concentration, it demonstrated a considerable improvement in the target compound degradation (at a NP/PS molar ratio of 1/4 kapp = 0.024 1/min) compared with the UVC photolysis (kapp = 0.016 1/min). Irrespective of the applied UV-induced treatment process, the efficacy of target compounds degradation was lower in groundwater as compared with ultrapure water trials. 相似文献
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分别用电镀法、爆炸法、电阻焊接法制备了三种钛基复合铂电极,并在电解法过硫酸铵生产作阳极挂槽进行电解运转试用,同时考察了这三种电极的使用寿命及使用效果。试用结果表明用电阻焊接法制备的钛包铂电极使用效果最理想,与传统的铝基铂电极相比,使用寿命长,可节约14%的能耗。 相似文献
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1,4-二氢-2,6-二甲基-3,5-吡啶二甲酸二乙酯无溶剂合成及其芳构化研究 总被引:2,自引:0,他引:2
介绍一种常规加热条件下无溶剂反应,短时间内一步合成了1,4-二氢-2,6-二甲基-3,5-吡啶二甲酸二乙酯的绿色工艺。分析了氮源、时间、温度对反应的影响,实验结果表明用醋酸铵为氮源,57℃左右无溶剂反应30min,顺利制得目标物,产率达88.15%。该文还发现,在少量丙酮和水的存在下,过硫酸铵室温(27%)下能迅速将1,4-二氢-2,6-二甲基-3,5-吡啶二甲酸二乙酯芳构化,n(二氢吡啶):n([o])=1:1,反应时间3~4min,产率超过97.20%。 相似文献
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