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随着现代化工业的快速发展,在工业的发展中废水的排放量越来越多,在这种背景下需要加强对废水的处理,保障废水经过处理之后能够实现有害物质减少,降低对人们的危害。在废水处理技术实施中,通过隔离废水,能够借助赤泥改性(PVDF)膜料对废水进行吸收,降低废水中的油性。本文在研究中通过实验分析,借助赤泥改性(PVDF)膜料对废水处理的影响进行了工业废水研究分析。希望在本文的研究帮助下,能够为废水处理中的赤泥改性(PVDF)膜料应用提供参考。 相似文献
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为了提高PVDF中空纤维膜在处理含油废水过程中的亲水性能、抗压实性能和抗污染性能,实验以介孔Al2O3为无机添加粒子,采用溶液纺丝法制备出介孔Al2O3/PVDF复合中空纤维膜。通过扫描电子显微镜和傅里叶红外光谱观察介孔Al2O3/PVDF复合中空纤维膜的形貌和成分,结果证明介孔Al2O3成功地添加到PVDF中空纤维膜中。通过接触角,纯水和含油废水通量的测试,结果表明介孔Al2O3的添加改善了PVDF膜的亲水性能、抗压实性能和抗污染性能。 相似文献
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聚偏氟乙烯(PVDF)膜因其优异的化学和力学稳定性而被广泛应用于水处理领域,但PVDF膜本身的疏水性,容易使其在处理含油废水的过程中被油滴污染,造成膜孔堵塞。以PVDF微滤膜为基底,通过单宁酸(TA)和聚乙烯亚胺(PEI)共沉积形成了TA/PEI黏附层,经戊二醛共价交联和接枝半胱氨酸(Cys),制备了一种PVDF改性膜(PVDF@TA/PEI-Cys)。改性后的PVDF膜具有良好的亲水性和水下超疏油性,水接触角和水下油接触角分别为22.2°和150.2°。在0.09 MPa下,PVDF@TA/PEI-Cys膜的纯水通量达6328 L/(m2·h),水包油型乳液分离效率高达99.9%。此外,该改性膜还可同时吸附水中的汞离子,最大吸附量为24.7 mg/g。 相似文献
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为提高支撑液膜萃取体系的稳定性,以苯乙烯为接枝单体、二苯甲酮(BP)为光引发剂,通过紫外接枝的方法对支撑体聚偏氟乙烯(PVDF)膜进行疏水改性,研究了制备改性膜的优化实验条件,对改性前后的PVDF膜的官能团、微观形貌和接触角进行了表征,并考察了原膜与改性膜构建的支撑液膜萃取体系处理含酚废水的能力。结果表明,制备改性膜的优化条件为:紫外光照时间15 min,反应温度30℃,接枝单体苯乙烯的质量分数4%,引发剂BP浓度0.3 mol/L。改性后的PVDF膜的接触角提高了76%,疏水性能显著提高。连续运行5次后,处理含酚废水改性膜除酚率比改性前提高了47%,体系运行更稳定。 相似文献
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废水处理不仅关系着我国环境污染的治理,同时也关系着水资源的重复、高效、循环利用。我国每年排放的含油废水高达几亿吨,若不及时、有效的对其进行处理,必将对人类健康以及社会生态系统产生巨大的危害。而近年来,膜分离技术在含有废水处理领域中的应用不断深入,但由于膜自身性能的限制,其取得的效果也比较有限。这种情况下,如何进一步改善、提高膜的抗污染能力,已经成为该行业领域亟待解决的主要问题。基于此,本文对膜材料领域中一种用于水处理的改性PVDF膜材料及其制备工艺进行了研究,同时通过对改性后的PVDF膜的性能进行检测,并将检测结果与纯PVDF膜的性能进行对比分析,以期更好的阐述该发明的优势。 相似文献
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Saturated very long chain fatty acids (fatty acids with greater than 22 carbon atoms; VLCFA) accumulate in peroxisomal disorders,
but there is little information on their turnover in patients. To determine the suitability of using stable isotope-labeled
VLCFA in patients with these disorders, the metabolism of 22-methyl[23,23,23-2H3]tricosanoic (iso-lignoceric) acid was studied in rats in vivo and in human skin fibroblasts in culture. The deuterated iso-VLCFA was degraded to the corresponding 16- and 18-carbon iso-fatty acids by rats in vivo and by normal human skin fibroblasts in culture, but there was little or no degradation in peroxisome-deficient (Zellweger’s
syndrome) fibroblasts, indicating that its oxidation was peroxisomal. Neither the 14-, 20-, and 22-carbon iso-fatty acids nor the corresponding odd-chain metabolites could be detected. In the rat, the organ containing most of the iso-lignoceric acid, and its breakdown products, was the liver, whereas negligible amounts were detected in the brain, suggesting
that little of the fatty acid crossed the blood-brain barrier. Our data indicate that VLCFA labeled with deuterium at the
ω-position of the carbon chain are suitable derivatives for the in vivo investigation of patients with defects in peroxisomal β-oxidation because they are metabolized by the same pathways as the
corresponding n-VLCFA. Moreover, as iso-VLCFA and their β-oxidation products are readily separated from the corresponding n-fatty acids by normal chromatographic procedures, the turnover of VLCFA can be more precisely measured.
A preliminary report of part of this work (Reference 18) was presented at the 5th International Symposium on the Synthesis
and Applications of Isotopes and Isotopically Labelled Compounds, Strasbourg, France, June 20–24, 1994. 相似文献
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为掌握佛山市顺德新城区降水中污染物的情况,2015年7月至8月,文章作者分别在雨天进行了降水取样,对降水中的pH、电导率、常见阴离子(F-、Cl~-、NO_3~(2-)、SO_4~(2-))及部分重金属(铅和镉)进行监测分析。选择有相关数据的珠江三角洲和石家庄、厦门等地的降水中污染物的情况进行对比。结果表明,顺德新城区降水中的p H和部分阴离子浓度优于珠江三角洲平均值,酸雨类型属于硫酸和硝酸混合型;其水体洁净程度略差于石家庄;铅和镉的浓度也高于厦门,甚至部分超出了人体能直接接触的安全范围。 相似文献
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H. Toda Y. Mochizuki T. Kawanishi H. Kawashima 《Nutrient Cycling in Agroecosystems》2002,63(2-3):167-173
In a coastal agricultural area in the central part of Japan (Shizuoka), we found decreasing nitrate concentration with depth in a shallow groundwater, where the depth to water table varied between 0.6 and 1.2 m below ground surface. High nitrate concentrations (5–29 mg N L–1) were often observed in the upper layer (0–2 m) of the groundwater, but the concentration decreased to less than 1 mg N L–1 in the deeper layer. Ammonium was scarcely detected, and the concentration of dissolved oxygen was usually low (< 1 mgO2 L–1) in the groundwater. Nitrate in the groundwater often had very heavy nitrogen stable isotope ratios (>20{}). There was a negative relationship between nitrogen stable isotope ratio of nitrate and its concentration. When nitrate was injected into the groundwater with acetylene and bromide (a conservative tracer), nitrate concentration decreased to 20% of the initial level within 5 days, accompanied by the increase in nitrite and nitrous oxide concentration and a little change in bromide concentration. These results indicate that microbial denitrification plays a potential role in the decrease of nitrate in shallow groundwater at the study site. 相似文献
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我国硝酸工业生产技术新进展 总被引:1,自引:0,他引:1
系统叙述了我国硝酸工业2000-2007年生产现状及主要技术成果,尤其指出了国产"四合一"机组的成功投运,使我国硝酸国产化装置取得较大的进步,表现在吨酸的铂耗、氨耗和能耗等方面接近国外引进装置水平,同时介绍了国外双加压法硝酸生产技术的进展.我国已成为硝酸生产大国,仍需以先进的技术改造和发展我国硝酸工业,确保我国硝酸工业健康有序地发展,加快从硝酸生产大国向强国迈进的步伐. 相似文献
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高效液相色谱法分析化妆品中微量成分的研究进展 总被引:1,自引:0,他引:1
综述了高效液相色谱法在化妆品中防腐剂、防晒剂中紫外线吸收剂以及性激素的检测等几个方面的应用;同时,介绍了分析所用的色谱柱、流动相、使用的检测手段以及样品的提取方法;最后针对目前存在的问题,提出了高效液相色谱用于化妆品中微量成分分析的研究方向和发展前景。 相似文献