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关键词： Ceramic microfiltration   Industrial dye wastewater   Adsorption   Membrane fouling   Organic dye  

摘要： In this study, combined effect of types of anionic dye compounds and solution pHs on organic removal efficiency and membrane fouling on the alumina-based microfiltration (MF) flat-tubular membrane was investigated using a laboratory-scaled, fluidized bed membrane reactor at constant permeate flux operation. For the Congo-Red dye solution at the solution pH of 6, there was no increase in suction pressure with only 10% of organic removal efficiency measured by ultraviolet-visible (UV-Vis) spectrometer during operational period. However, lowering the solution pH to 4.5 accelerated suction pressure increase while higher than 90% organic removal efficiency was achieved. At the solution pH of 4.5, a zwitterion nature characterized by Congo-Red dye compound resulted in more deposit of cake layer on membrane than that formed at higher pH. In the case of Tartrazine and Acid Orange 7 which are categorized as anionic dye compound, the increase in suction pressure with time was much slower than that observed with Congo Red at same solution pH (4.5) and permeate flux (40 L m(-2)h(-1)). Our results suggested that higher fouling rate should be associated closely with higher organic removal efficiency in ceramic MF membrane filtration. Regardless of types of dye compounds tested, granular activated carbon (GAC) fluidized in submerged ceramic membrane reactor was found to be propitious tool to reduce membrane fouling with excellent organic removal due to adsorption functionality and scouring action provided by GAC fluidization on membrane. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Quartz  

摘要： The Huzhagaitu molybdenum deposit is a newly discovered porphyry deposit in the middle segment of the Derbugan metallogenic belt in Inner Mongolia. The molybdenum orebodies are mainly hosted within the Early Yanshan granodiorite, and its contact zone with rhyolite. The deposit is dominated by molybdenum mineralization and pyrite mineralization, accompanied by lead-zinc mineralization and a small amount of copper mineralization. The ore-forming process can be divided into four stages: silicification stage, quartz-molybdenum stage, quartz-polymetallic sulphide stage, and quartz-calcite stage. There are four types of fluid inclusions: liquid-rich phase inclusions, vapor-rich phase inclusions, multiphase inclusions including daughter minerals and CO2-bearing three-phase inclusions. With the main mineralization stage as the focus of our research, this study carried out microscopic temperature measurement and laser Raman microprobe analysis for the inclusions in quartz or calcite in different mineralization stages (stage II to IV). The results show that the homogenization temperatures of the inclusions in the quartz-molybdenum-pyrite stage are mainly concentrated between 280℃ and 400℃, and the salinities vary from 2.57% to 51.68%. In this stage, vapor-rich phase inclusions and multiphase inclusions including daughter minerals coexist with CO2-bearing three-phase inclusions. The liquid phase composition of L-type inclusions is mainly H2O-NaCl. The gas phase composition of V-type inclusions is mainly H2O, and some of them also contain CO2. Characteristic peak of laser Raman shift of daughter mineral chalcopyrite was detected in halite-bearing three phase inclusions. In the quartz-pyrite stage with lead-zinc mineralization and chalcopyrite mineralization, the homogenization temperatures of the inclusions are concentrated between 180℃ and 280℃, and the salinities vary from 0.18% to 9.73%. In late stage, only L-type inclusions occur in quartz-calcite veins, with the homogeniza

关键词： Semi-classical Theory   Superfluid density   Anisotropic gap function  

摘要： In this research, we investigated the superfluid density of anisotropic S-wave superconductors by Semi-classical Theory in 3D spherical Fermi surface. The anisotropic gap function was studied by ellipse spherical and pancake spherical model. The superfluid density was derived analytically and applied to MgB2 and CaAlSi superconductors. We found that CaAlSi superconductors show the properties of anisotropic one band S-wave superconductors but the MgB2 superconductors cannot fit well with our model.

关键词： Fluidized bed drying   vacuum-drying   freezing pretreatment   carrot   shrinkage   rehydration  

摘要： A method for low-temperature drying with high drying rate was developed for heat-sensitive foods and agricultural products. A freezing pretreatment was combined with fluidized bed drying under reduced pressure. Cylindrical carrot samples were frozen and then placed without thawing in a fluidized bed of hygroscopic porous silica gel particles that adsorbed water from the sample during the drying process. The effects of the freezing pretreatment and hygroscopicity of fluidizing particles on the drying characteristics of carrots were examined. A higher drying rate was achieved when carrots samples were subjected to freezing pretreatment than without it. At 12kPa, the volume change was smaller in carrots subjected to freezing pretreatment than in untreated samples. A larger amount of water was absorbed during rehydration by carrots dried at 12kPa than at 101kPa within 120min. The properties of dried carrots were affected not only by freezing pretreatment but also by the pressure applied during the drying process.

关键词： 表面物理化学   开尔文计算公式   表面张力  

摘要： 表面物理化学是研究两相之间界面上发生的物理化学过程的科学。自然界中的许多现象都与界面的特殊性质有关,当物质被分散时,分散度越高,其表面积就越大,表面效应也就越明显。如雨滴露珠,各式商品,工业技术,以及纳米科学和纳米技术,无不与表面化学密切相关。现以开尔文计算公式的推导为例,应用物理化学的基本理论,对界面的特殊性质及现象进行探讨和分析,旨在提高物理化学教学效果,帮助学生理解和深化有关知识。

关键词： 重力   中水   水膜   体验生活   表面张力   睡袋   上学   环境  

摘要： 呀,我怎么睡在墙上?仔细一看,原来是在挂在墙上的睡袋里.这是哪里?哦,我想起来了,我是随科学家杨伯伯来到宇宙空间站,将在这里体验生活,并上学一天.我紧抓着扶手去洗漱.怎么回事?水怎么成了一层膜贴在脸上?杨伯伯说:'因为远离地球,这里没有重力,在失重环境中水的表面张力变大,就变成了水膜,所以只能用湿毛巾擦脸.'刷牙的时候,杨伯伯告诉我要把水咽下去,如果吐出来,水就会成为水珠飘浮在空中.我心中暗暗不快,牙膏水真难喝.

关键词： 聚乙烯-聚丙烯非织造布   亲水油剂   表面张力   动态接触角   表面活性剂  

摘要： 针对亲水油剂研发过程中表面活性剂配伍与聚乙烯-聚丙烯(ES)非织造布亲水性关系的问题,借助稳态荧光猝灭法、视频接触角测定仪、液体穿透时间测定仪等,考察了油剂或表面活性剂的溶液表面张力、胶束聚集数、聚集体粒径分布、聚乙烯(PE)界面动态接触角等性能指标,探讨了表面活性剂结构和协同配伍与ES非织造布多次透水时间的关系,测试了亲水油剂的综合性能。结果表明:亲水油剂的高表面活性、较小的亲水疏水平衡值(HLB值)、较大的胶束聚集数以及有效成分与ES纤维间的强吸附力等均有利于提高ES非织造布亲水性;改性后ES非织造布3次透水时间均小于3 s,反湿量小于0. 13 g,表面比电阻小于3. 0×108Ω·cm,已达到卫生用品覆面材料的要求。

关键词： 微量元素   稀土元素   成矿流体   居隆庵和沙洲铀矿床   相山铀矿田  

摘要： 相山铀矿田的成矿流体性质和来源存在争议,为进一步探讨相山铀矿田成矿流体的性质和来源,本文对相山铀矿田西部的居隆庵铀矿床和北部的沙洲铀矿床中的新鲜围岩、蚀变围岩及矿石的微量、稀土元素含量及其变化进行了研究。结果显示:在含较多热液成因萤石的居隆庵铀矿床中,从新鲜围岩到蚀变围岩到矿石,Zr、Hf含量先降低再升高;而在含少量热液萤石的沙洲铀矿床中,新鲜围岩、蚀变围岩和矿石的Zr、Hf含量基本一致。鉴于富F流体易汲取岩石中的Zr、Hf,因此,这两个矿床中不同类型样品Zr、Hf含量的不同变化趋势,可能与居隆庵铀矿床的成矿流体富F、而沙洲铀矿床的成矿流体相对贫F有关。这两个铀矿床中矿石的稀土配分曲线与其各自的新鲜及蚀变围岩的稀土配分曲线形态相似但又存在差异,说明每个矿床的新鲜围岩、蚀变围岩和矿石之间的稀土元素既具有继承性、又受到不同性质的流体的影响。居隆庵铀矿床中矿石显示Eu负异常,可能主要是继承了围岩的Eu负异常;沙洲铀矿床中矿石Eu显示弱负异常至弱正异常的特征,可能与围岩中斜长石因热液蚀变作用而释放出的Eu的进入流体有关。基于新鲜围岩、蚀变围岩及矿石的U和REE研究,推断居隆庵铀矿床成矿流体中U和REE均以F的络合物形式迁移;但沙洲铀矿床中铀矿石品位较低,可能是与流体中相对贫F有关。

关键词： 青海双朋西   金矿   流体演化   找矿方向  

摘要： 青海双朋西金矿位于青海省黄南藏族自治州同仁县境内,金矿床的主要形成类型分为辉长岩和矽卡岩,花岗岩和大理岩接触带的矽卡岩是金矿床的主要产区。基于青海双朋西区域内的金矿地层和构造情况,对金矿成矿流体演化特征进行分析,并提出该区域内金矿的找矿方向,为今后找矿工作提供参考。

关键词： 地下流体异常   中国震例   异常特征  

摘要： 从1967年至2013年华北、东北地区共发生的41次中强以上地震中,统计了各地震发生前187项地下流体异常变化特征。结果表明,震前出现的地下流体异常中,水氡、水位异常出现的时间范围较广,在震前几年至十几分钟内均有出现,异常开始距发震时间、异常出现范围和时间与震级大小、异常变化类型等有关。异常台站震中距范围可达500km,异常形态主要包括上升、下降、突跳和破年变等4类,其中上升、下降、破年变异常动态主要表现为中期异常,突跳型异常动态主要表现为短临异常。