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101.
《分离科学与技术》2012,47(14):3101-3116
Abstract

In this study, the performance of GAC adsorption and biofiltration systems in treating biological treated sewage effluent (BTSE) was evaluated in terms of organic removal efficiency, organic fractions, and molecular weight distribution (MW) of organic matter (OM) removed. The GAC biofilter removed 23.5% and 61% of the hydrophobic fractions and hydrophilic fractions of OM in the BTSE respectively. MW distribution studies of GAC filter and GAC adsorption revealed the following: Hydrophobic fraction of the effluent showed a peak at 345 dalton after GAC biofiltration and 256 dalton after GAC adsorption, whereas, with hydrophilic fractions, peaks at 46,178 and 345 daltons were observed after GAC biofiltration and peaks at 46,178 and 256 daltons after GAC adsorption. Transphilic fraction showed the peaks at 12,783 dalton with GAC biofiltration, and 1,463 dalton with GAC adsorption. The performance of the GAC biofilter was successfully mathematically modelled.  相似文献   
102.
Modification of a selective area of a fluororesin surface was accomplished by using ArF excimer laser radiation and a boron complex with oleophilic or hydrophilic functional groups. The chemical stability of fluororesin is attributed to the presence of C-F bonds. The F atoms were abstracted by B atoms selectively from the area irradiated with excimer laser radiation and were replaced with the desired functional groups. In this modification, B(CH3)3 and B(OH)3 were used: a boron compound with methyl groups to generate an oleophilic surface, and one with hydroxyl groups to generate a hydrophilic surface. As a result, the resin surface exposed to ArF laser radiation becomes oleophilic or hydrophilic. Both samples were bonded to stainless steel plates with an epoxy bonding agent and the tensile shear strength was 1.2 x 107 Pa in both cases.  相似文献   
103.
Corona discharge has been widely applied to modify the surfaces of polymers. In this study, corona discharge was combined with a hydrogen peroxide treatment to improve the hydrophilic properties of wool fabric. Scanning electron microscopy photographs showed that the tip of wool scales was etched after corona discharge and that parts of the scales were peeled off after the hydrogen peroxide treatment. The surface hydrophilic properties of the wool fabric were improved greatly by corona discharge. Increases in the discharge voltage and the number of treatment passages enhanced the hydrophilic properties dramatically, but the improved properties deteriorated with increases in the number of washing cycles and storage time. The hydrogen peroxide treatment could improve the hydrophilic properties and especially the wicking properties of the wool fabric. The fabric became weaker and flexible with an average weight loss of 3% after the hydrogen peroxide treatment. A combination of corona discharge treatment and the hydrogen peroxide treatment made the wool fabric absolutely hydrophilic; the water penetration time of the treated fabric was less than 1 s even when the fabric was washed for several cycles or stored for 6 months. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
104.
BREAST fibromatosis is a rare kind of lesion.The average incidence is about 2-4 per million every year.1 So far there have been about 100 cases reported altogether.2 In this report, we describe a case of breast fibromatosis developed after hydrophilic polyacrylamide gel (HPG) injection for breast augmenta-Received for publication December 10, 2010.  相似文献   
105.
非织造布亲水整理及亲水剂   总被引:9,自引:2,他引:7  
本文主要介绍非织造布亲水整理的实际意义、原理及亲水剂 ,指出提高非织造布的亲水性是改善产品使用性能、提高产品附加值的重要手段 ,应给予高度重视  相似文献   
106.
通过改变分散剂的种类和用量,引发剂的用量及聚合反应时间等实验条件,在能获得轴向流型的聚合反应釜中,烯丙基葡聚糖与N,N‘-亚甲基双丙烯酰胺可以悬浮聚合,形成分布较窄的珠状亲水层析凝胶。  相似文献   
107.
谢文娜  周兰姜  黄宏伟  郭孟萍 《应用化工》2014,(11):1958-1961,1964
以对氯苯乙酮为起始原料,采用对空气和潮气稳定的水溶性钯(Ⅱ)催化剂在纯水中100℃下,通过Suzuki偶联合成联苯乙酮,再经Willgerodt-Kindler反应制得联苯乙酸。通过考察温度、时间、碱、催化剂和物料比等因素对两步反应的影响,确定了合成联苯乙酸较为理想的工艺条件。产品总收率71.6%。  相似文献   
108.
黄建华 《城市建筑》2014,(14):293-294
本文以城市公园亲水空间的安全问题作为研究对象,从亲水空间景观元素的潜在安全隐患(物的不安全状态)和基于安全角度的游人环境行为(人的不安全行为)两个方面进行研究。并利用鱼刺图对城市公园亲水空间的潜在安全隐患进行了较为完整的梳理分析,最后提出了潜在安全隐患的消除途径。  相似文献   
109.
Objective: The aim of the present investigation was to evaluate the use of spray-dried O-carboxymethyl chitosan (OCMCS) as potential hydrophilic matrix excipient for sustained release of drug.

Methods: The polymer was synthesized from chitosan, then spray-dried and characterized. Tablets with different OCMCS concentrations (80, 50, 30, 5 and 2% w/w), containing diltiazem (DTZ) as model drug, were prepared for direct compression (DC) and after the wet granulation method (WG).

Results: The spray-dried OCMCS powder was spherical, with a smooth surface and an average size of 2.2?µm. The tablets prepared for WG disintegrated in time less than 30?min. The tablets obtained for DC presented high retention of the drug, with zero order or Higuchi release kinetic. There was a direct relationship between the OCMCS concentration and the release ratio, swelling degree and water uptake behavior. DC tablets containing 80% OCMCS presented behavior as an effective swelling-control system. The DC tablets with 5% OCMCS showed a similar release profile at formulations with 30% HPMC.

Conclusion: Spray-dried OCMCS showed great potential as hydrophilic matrices for drug-sustained release.  相似文献   
110.
亲水性固结磨料研磨垫(FAP)的自修整过程影响着其加工性能的稳定性.采用亲水性树脂和铜粉制备固结磨料研磨垫,研究研磨液中添加不同含量三乙醇胺对树脂基体砂浆磨损率及研磨垫材料去除率大小、稳定性的影响,以此来判断研磨垫的自修整性能,探索亲水性固结磨料研磨垫自修整的实现机理.结果表明:在本文实验所考察范围内,随着研磨液中三乙醇胺含量的增加,树脂基体的砂浆磨损率升高,当三乙醇胺体积比从0升至5%时,砂浆磨损率从0.003 3 g上升至0.009 1 g;研磨液中三乙醇胺浓度的提高有助于其材料去除率的稳定,当三乙醇胺体积比从0升至5.0%时,材料去除率的稳定性从11%提升至42.9%.可见,研磨液中加入三乙醇胺可以改善含铜粉亲水性固结磨料研磨垫的自修整性能.  相似文献   
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