A/O MBR(一体式)系统处理印染废水

设计一套A／O MBR（一体式）系统处理印染废水，通过四个阶段的连续运行，对其COD、色度、SS、浊度等指标进行监测，确定最佳运行条件为HRT=9～10h，DO=2～3g／L，在此条件下处理后可使印染废水的COD≤100mg／L，色度=2～16倍，浊度≈0，SS≈0，pH=7～8．5，结果表明A／OMBR（一体式）系统费用低、效果好，其中A／O系统可提高印染废水的可生化性，利于后续MBR的处理，最终使印染废水实现达标排放。     

Fenton试剂法深度处理皮革废水生化出水的研究

以加工生牛皮为主的皮革厂废水处理站生化出水为研究对象．研究了Fenton试剂对此废水的处理效果及影响因素。试验确定降解此类皮革废水生化出水的最佳条件为：pH值5．0,H2O2投加量600mg／L,Fe^2＋的投加量500mg／L,反应时间50min,在此条件下,当进水COD的质量浓度为333mg／L,色度为90倍时,COD和色度的去除率分别达到73．30／da98％。废水COD的质量浓度降至89mg／L,色度降至5倍以下,达到〈污水综合排放标准〉（GB8978-1996）皮革废水一级标准。     

Fenton—PAM联合处理焦化废水

首先用活化粉煤灰预处理焦化废水,COD去除率最大可达17％。然后利用Fenton试剂和PAM联合作用对焦化废水深度处理,单因素实验和正交试验结果表明,当pH=5,H2O2投加量为3mL／L,FeSO4·7H2O的投加量为6g／L,PAM的投加量为0．5g／L,反应时间为2h,处理效果最佳,COD和色度的去除率分别可达去90．8％和91．25％。各因素对COD去除率影响的强弱顺序为：PAM投加量〉pH值〉H2O2投加量〉FeSO4·7H2O投加量。     

微电解-光催化氧化法处理印染废水

采用微电解-光催化法对印染废水的处理进行了研究。结果表明：当进水COD为2000mg／L左右，色度为800-1000倍时，经本法处理的废水，出水COD为150～180mg／L，色度为0～10倍，COD去除率达92％，脱色率接近100％。主要水质指标达到了GB8978-1996《污水综合排放标准》中染料工业的二级标准。研究了一些因素对处理过程的影响。     

臭氧氧化法处理煤化工难降解废水实验研究

某煤化工废水经生物处理后COD仍然在500mg／L以上,色度较大,为保证后处理排水达标,对该废水进行臭氧氧化处理。经实验,处理1L废水时的最佳反应条件为进气流量0．6m3／h,产臭氧量7．73mg／min,气循环1．0m3/h,反应时间30min。处理后COD去除率为30％,废水B／C达到0．3,色度达80％。     

酸性嫩黄染料废水臭氧氧化处理的试验研究

依据臭氧高级氧化的机理,在实验室反应器中通过实验考察在臭氧氧化处理酸性嫩黄染料废水过程中,控制不同的O3投加量、废水的初始pH值、H2O2与O3摩尔比对酸性嫩黄染料废水的色度和COD去除率的影响。结果显示：O3高级氧化能够有效降解酸性嫩黄染料废水,体系中投加H2O2可以提高降解速率,缩短处理时间,降低O3耗量。在pH=7的条件下,单一臭氧氧化30min时,废水的色度和COD去除率分别为100％和57．1％;而提高废水的pH值有助于提高COD去除率。O3／H2O2氧化工艺,适宜的H2O2与O3摩尔比为0．6,氧化处理30min废水的COD去除率可达73．3％。     

用复相光催化剂WO3/CdS/W深度处理印染废水的研究

用复相光催化剂WO3／CdS/W对印染废水的深度处理进行了研究，探讨了光 经反应机理，讨论了复相光催化剂的组成，用量，试液pH值，光照时间与COD，色度去除率的关系。实验结果表明：以WO3／CdS/W为复相光催化剂，其组成为WO3／CdS/W=60:39:1，用量＝0．300g，试验pH＝6．5，光照10h，印染废水的COD，色度去除率分别达到69．8％和71．0％。     

改性粉煤灰对有机废水的吸附试验研究

将粉煤灰改性后对印染废水进行了吸附研究,找到较好的工艺条件与吸附效果。结果表明：对于COD20～150mg／L的印染废水溶液,粉煤灰用量以40g/L为宜,pH值为4．0,脱色率在32％以上。用0．1mol／L硫酸改性粉煤灰吸附印染废水的pH为4．0,投加量为24g／L,脱色率在47％以上,吸附处理后染料废水COD为76mg／L,COD去除率为21％。     

微电解-光催化氧化法处理印染废水

采用微电解-光催化法对印染废水的处理进行了研究。结果表明：当进水COD为2000mg／L左右,色度为800～1000倍时,经本法处理的废水,出水COD为150180mg／L,色度为0～10倍,COD去除率达92％,脱色率接近100％。主要水质指标达到了GB8978—1996《污水综和排放标准》中染料工业的二级标准。研究了一些因素对处理过程的影响。     

改性膨润土处理印染废水的研究

膨润土矿主要组分蒙脱石具有独特的晶体结构，拥有良好的阳离子交换性能和高比表面积等特性。但膨润土直接用于处理染料废水几乎没有处理效果，在使用前须进行转型和改性。本研究的目的是通过对膨润土的改性，提高其对染料废水的处理效果。改性膨润土吸附剂在投加量为2．5g／L时，处理实际印染废水，可使COD为1227mg／L、色度为260的印染废水脱色率达到95％以上，COD去除率达到56％。     

磁选技术在水污染治理中的应用

磁分选技术因其操作简单、分选能力强、应用范围广、不产生二次污染等特点,在污水净化、水资源循环利用等领域的应用日益增多。本文综述了近年来国内外磁选技术在水污染治理中的应用研究进展;同时对水治理磁分离新技术--超导磁选、磁泳分离、磁种-絮凝磁选、磁场辅助膜分离等作了介绍,并探讨了磁选技术的发展方向。     

密度组成及磁场强度对煤比磁化率影响的研究

不同密度级煤比磁化率的差异是煤磁选的依据,用Gouy磁天平对不同密度级煤比磁化率进行测定,煤比磁化率随着密度的减小而减小,小于1.5 g/cm3密度级的煤显逆磁性;低密度级煤比磁化率随着磁场强度的增加而减小,逆磁性增加,而高密度级煤比磁化率随着磁场强度增加顺磁性减弱.根据所得函数式,表明存在一最佳磁场强度使低、高密度级煤的磁性差异最大.相比较而言,密度对煤磁化率的影响更大.     

低温热解强化煤粉磁选脱硫效果的实验研究

采用自制热解装置对北宿煤进行热解,此装置与传统热解装置相比具有处理量大和操作简便等优势,能够与磁选实验相结合,热解温度400 ℃～700 ℃,氮气流量0.1 L/min,保温时间为30 min,主要研究热解温度对煤粉磁选脱硫效果的影响.结果表明:适当提高热解温度对磁选脱硫是十分有利的,且500 ℃时效果最佳,热解后半焦与原煤相比磁选脱硫率提高近40%;利用XRD分别对原煤、500 ℃半焦及半焦磁选后的精煤进行分析,发现半焦中有强磁性矿物磁黄铁矿(Fe1-xS)生成,精煤中已无黄铁矿,说明热解-磁选脱硫技术能够有效脱除煤中无机硫.依据GB/T215-2003分析试样中硫的形态,发现煤中有机硫含量高且以噻吩硫形式存在,给实现北宿煤低温预处理磁选高效脱硫造成了困难.     

交变磁场对重力SHS制备复合管微观结构和机械性能的影响(英文)

将交变磁场引入自蔓延高温合成反应,研究其对Al2O3复合管陶瓷层结构和力学性能的影响.结果表明:交变磁场可以促进燃烧反应的进行,随着磁感应强度的增加,α-Al2O3的枝晶尺寸减小,形态逐渐向细小的等轴晶形态过渡.复合管的抗压强度和抗剪强度随着磁感应强度的增加而增加.其中当磁感应强度为0.20T时,抗压强度和抗剪强度分别达418MPa和19.5MPa,比未引入交变磁场前分别提高了19.1%和21.9%.     

AGGREGATION IN MAGNETIC FLUIDS AND MAGNETIC FLUID COMPOSITES

Many of the properties of magnetic fluids and magnetic fluid composites can be explained by the presence of aggregates of particles. In this paper, the experimental methods by which these properties can be studied are reviewed. Theoretical methods of predicting these properties, and the particle size and magnetic field dependence of the formation of aggregates are also presented.     

MAGNETIC POLYSACCHARIDES

Magnetic composites with superparamagnetic properties has developed a great scientific interest in the last years by their potential application in drug delivery and cell sorting systems. Alginate, starch and chitosan were used as polymeric matrixes in order to obtain magnetic nanostructured composites. Magnetic nanocrystalline particles of iron oxide were formed inside the matrix by an in situ alkaline oxidation of iron (II) ions. The total iron content was determined in each composite. X-Ray Diffraction, Magnetometry and Mössbauer Spectroscopy were used to examine the composites. The magnetic materials exhibits high magnetic response, absense of hysteresis in the magnetization curves and a centered paramagnetic doublet in the Mössbauer spectra indicating the presence of nanocrystalline particles with a superparamagnetic behavior. X-Ray diffractograms show peaks that correspond to maghemite.     

新型碳纳米管磁性复合材料的制备及磁性能

采用水热-沉淀法制备了ZnFe2O4包覆碳纳米管(carbon nanotubes,CNTs)磁性复合材料.采用X射线衍射、扫描电镜、透射电镜、Mǒssbauer谱仪和振动样品磁强计等仪器表征制备样品的结构与性能.200℃是制备纳米ZnFe2O4包覆CNTs磁性复合材料的较好的反应条件,温度过高或过低都生成较多的γ-Fe2O3.包覆在CNTs上的ZnFe2O4纳米粒子为球形,粒径为13～20nm.Mǒssbauer谱结果表明:大部分znFe2O4纳米粒子表现出超顺磁性,少量表现出铁磁性.磁滞回线结果表明:复合材料的矫顽力值为254215.85A/m.     

LONG-RANGE MAGNETIC FORCES IN TWO-DIMENSIONAL HYDRODYNAMICS OF MAGNETIC FLUID PATTERN FORMATION

Phenomena associated with long-range forces of interparticle interaction have received great attention since the stable colloids of ferromagnetics were first prepared. One of these-surface instability of magnetic fluid in a vertical field-was first observed by Cowley and Rosensweig (Cowley, Rosensweig, 1967) and is a remarkable demonstration of the properties of liquid magnetics. The studies here have displayed a lot of interesting characteristics of these phenomena such as subcritical character of bifurcation at the origin of hexagonal pattern of a magnetic fluid (Gailitis, 1969), a possible change of hexagonal pattern into the square one (Gailitis, 1977; Kuznetsov el al., 1976), subcritical bifurcation of a uni-dimensional pattern (Zaitsev et al., 1969; Bacri et ai., 1984).

The development of a concept of the hydrodynamical stability control by the field has demonstrated the stabilizing effect of a magnetic field at both the Rayleigh-Taylor instability (Rosensweig, 1979a) and the Saffman-Taylor instability of displacement front (Rosensweig et al, 1977; Zahn et al, 1980) and others. Using this basis, Rosensweig was able to put forward an alluring idea of possible application of magnetic forces to stabilize ftuidized beds (Rosensweig, 1979b, 1979c). It is the significant contribution of Rosensweig's works into further investigations of the hydrodynamic instability control by a magnetic field, which should be given a special mention. These developments have lead to new insights and will add a new dimension to the study of magnetic fluids.

We shall consider a comparatively new type of two-dimensional hydrodynamical instability revealing an intricate pattern of selforganization of a magnetic fluid due to long-range magnetic forces.     

MAGNETIC MEASUREMENTS ON FERROFLUIDS

Magnetic measurements on ferrofluids can be used to determine the magnetic concentration which may be as large as 15% by volume in a very viscous fluid. Additional information on the particle size distribution parameters and the mode of magnetisation can be obtained from an analysis of the magnetisation curve. Magnetic studies are also invaluable for a correct interpretation of the magnetic dichroism, birefringence and small angle neutron scattering (SANS) data. Measurements on a ferrofluid after freezing enables the shape anisotropy to be determined and the degree of particle elongation (∼15%) calculated.     

不同磁粉含量对磁性PP纤维性能的影响

采用皮芯层复合纤维纺丝机纺制不同磁粉含量的聚丙烯 (PP)磁性纤维 ,对纤维的纺丝性能、拉伸性能、热性能进行了研究。结果表明 :随着磁粉含量的增加 ,磁性纤维的纺丝性能、拉伸性能、热性能下降。选择磁粉和聚丙烯的合理配比 ,既可以提高磁性纤维的纺丝性能、拉伸性能和热性能 ,又可以提高磁性纤维的磁粉含量。