改性花生壳活性炭吸附-催化臭氧氧化处理反渗透浓水

考察了改性活性炭吸附-催化臭氧氧化对炼化RO浓水中有机污染物的降解效果。结果表明,花生壳经H_3PO_4活化后具有较好的比表面积及孔径结构,再经Cu~(2+)、Mn~(2+)、Fe~(3+)溶液负载改性,得到花生壳活性炭催化剂,其中Cu~(2+)改性后的活性炭具有最大的比表面积。将不同的改性活性炭与臭氧组合处理RO浓水,COD去除率显著提高,表现为CuAC≥Mn-ACFe-ACH_3PO_4-AC,偏碱性条件和提高活性炭投加量均利于活性炭吸附-催化臭氧氧化反应,且在30 min后COD去除率趋于平稳。当利用金属离子负载改性活性炭时,臭氧消耗率显著提高。其中,Cu-AC和Mn-AC吸附-催化臭氧氧化时臭氧的消耗率较高,COD去除率≥80%,出水COD60 mg·L~(-1),达到国家一级排放标准。     

一种污泥活性炭的制备及其在兰炭废水处理中的应用

以城市生活污水厂脱水污泥和木屑的混合物为原料,利用ZnCl_2为活化剂制备污泥活性炭。研究了活化温度、活化时间、固液比和活化剂浓度对吸附性能的影响。在活化温度为650℃、活化时间30 min、固液比1∶1.5、活化剂浓度为5 mol·L~(-1)的最佳工艺条件下,制备得到的活性炭碘吸附值为584.85 mg·g~(-1),利用扫描电镜可以观察到其发达的孔隙结构。将制备的污泥活性炭应用于兰炭废水处理中,结果表明,污泥活性炭的投加量为180 g·L~(-1),pH为7,吸附时间60min,挥发酚和氨氮的去除率分别为73.38%和48.27%,废水中污染物浓度明显降低。     

造纸污泥制备功能吸附材料及其对Cu2+吸附性能的研究

以造纸污泥为原料,利用热解的方法制备生物炭,然后用氢氧化钠对其改性,得到功能吸附材料(SAM),探讨了SAM对Cu~(2+)的吸附性能及其影响因素。采用扫描电镜(SEM)、红外光谱等手段揭示了SAM吸附Cu~(2+)的机理。结果表明:造纸污泥在300℃热解2h,然后用5mol/L的氢氧化钠改性,可制备得到对重金属具有良好吸附性能的SAM;当100mg/L的Cu~(2+)模拟废水的pH为6～7时,SAM投加量为0.010 0g/mL下Cu~(2+)去除率为99.15%,SAM投加量为0.002 5g/mL下SAM的吸附量为28.788mg/g;SAM吸附Cu~(2+)符合Langmuir吸附等温模型,属于单分子层吸附,其吸附机理主要表现为化学吸附,即SAM中含有丰富的羟基官能团,Cu~(2+)能与羟基形成稳定的络合物,通过化学键固定在SAM的表面及孔内,从而达到去除模拟废水中Cu~(2+)的效果。     

铁盐改性砂制备及其吸附Zn~(2+)的性能研究

通过改变石英砂表面的物理化学性质,提高石英砂的吸附效率,考察其对废水中的Zn~(2+)去除效果.以石英砂为载体,分别用反复高温加热法和反复碱性沉积法制备了三氯化铁改性砂、硝酸铁改性砂,测定2种方法制备的铁盐改性砂的表面含铁量、铁盐的酸稳定性及比表面积,并比较2种铁盐改性砂对Zn~(2+)的吸附效果.结果表明,三氯化铁改性砂、硝酸铁改性砂的比表面积分别为2.468、4.247 m~2/g,比石英砂比表面积分别提高6.910、12.612倍;在pH为中性条件下,石英砂对Zn~(2+)去除率为43%左右,三氯化铁改性砂对Zn~(2+)去除率达到70%左右,硝酸铁改性砂对Zn~(2+)去除率达到85%左右,表明铁盐改性砂对Zn~(2+)去除能力比石英砂有很大提高;铁盐改性砂对Zn~(2+)的吸附有一定容量,表面的活性中心越多,吸附能力越大;铁盐改性砂对Zn~(2+)的去除率随着pH的升高而增加,当pH>8.5时,Zn~(2+)去除率可达90%左右.     

催化氧化法处理铜氰废水

采用催化氧化法,对Cu~(2+)<15mg/l,CN~-<25mg/l,Cu~(2+)/CN~-摩尔浓度比在0.1～0.7的铜氰废水进行处理。反应条件控制在:pH7.0～8.5,滞留时间45分钟,液固比在0.7～1.5ml/g,空气容量为30～50ml/l。在S催化剂作用下,处理后出水Cu~(2+)和CN~-浓度可符合排放标准。本装置处理费用0.07元/吨。再生简单,操作方便。     

微波辐照废木屑活性炭制备工艺优化及其应用

以微波为热源,Na2CO3为活化剂,采用化学活化法制备废木屑活性炭（AC）。采用Taguchi法考察了微波辐照功率、辐照时间、活化剂浓度、固液比对活性炭碘吸附值的影响。结果表明,微波辐照功率对活性炭碘吸附值的影响最显著,辐照时间次之,而固液比的影响不显著。优化的工艺参数为微波辐照功率440W、辐照时间9min、Na2CO3浓度15％、固液比1：2．5,该条件下AC的碘吸附值为1230．40mg／g,实验结果验证了Taguchi法的有效性。该条件下制得的AC用于处理印染废水,结果显示,对COD为239．5mg／L废水投加3g／L活性炭,在pH为11时吸附70min,COD的去除率达77．9％。     

改性硅藻土/纳米零价铁复合材料去除水中Cu~(2+)的研究

应用改性硅藻土(CDt)/纳米零价铁(NZVI)复合材料对水溶液中的重金属Cu~(2+)进行去除研究。结果表明,CDt/NZVI能高效去除水中Cu~(2+),在CDt/NZVI投加量为0.075g、pH=5、Cu~(2+)初始质量浓度为20mg/L、溶液体积为100mL时,Cu~(2+)去除效果最好,去除率达到98.52%。CDt/NZVI对Cu~(2+)的去除机理包括吸附和还原,吸附过程符合Langmuir方程,最大吸附量为74.29mg/g;还原产物主要为Cu_2O和Cu~0。CDt/NZVI具有良好的循环利用性,循环3次后Cu~(2+)去除率仍能保持在65%以上。     

微生物燃料电池处理含铜废水的研究

构建了以乙酸钠为阳极基质、Cu~(2+)为阴极电子受体的双室微生物燃料电池(MFC),考察了该MFC处理含铜废水的效果及Cu~(2+)浓度对MFC产电性能的影响。通过改变阴极液中CuSO_4的质量浓度(20~130mg/L),测试了MFC运行过程中的输出电压、输出功率密度、内阻、Cu去除率等指标。结果表明:Cu~(2+)可作为MFC的阴极电子受体;在外电路电阻为1 000Ω的条件下,Cu~(2+)质量浓度为130mg/L的MFC性能最佳,其稳定输出电压为0.33V、最大输出功率密度为114.42mW/m~2,内阻为231.62Ω,最高Cu去除率为84.59%;通过X射线衍射测试发现,阴极还原产物为Cu_2O。     

新型高分子絮凝剂黄原酸化壳聚糖的制备及除铜性能

以壳聚糖(CTS)为原料,先用苯甲醛保护其C_2位上的氨基生成Schiff碱壳聚糖,再将二硫代羧基通过黄原酸化反应接枝到CTS C_6位羟基上,制备出一种新型高分子絮凝剂——黄原酸化CTS(XCTS)。采用单因素实验法考察了XCTS制备的影响因素及其制备条件,并探讨了水样中Cu~(2+)初始浓度、pH对XCTS除铜性能的影响。结果表明,当XCTS制备条件为CS_2用量2.0mL、NaOH浓度5.0%(质量分数)、预反应温度30℃、预反应时间30min、主反应温度60℃、主反应时间240min时,制得的XCTS除铜性能最好,Cu~(2+)的最高去除率可达97.7%。XCTS最佳投药量随着水样中Cu~(2+)初始质量浓度的增加而增加;Cu~(2+)的去除率随着水样pH(pH不为7.0时)升高而先增大后减小,水样pH为6.0时,Cu~(2+)去除效果最佳。     

新型微电解填料-Fenton联用处理硝基苯废水

研究通过单因素分析和正交实验法确定新型微电解填料-Fenton联用预处理硝基苯废水的最佳操作条件。结果表明,新型微电解填料降解硝基苯的影响因素从大到小依次为固液比 > 进水pH值 > 气水比 > HRT,在微电解最佳条件:HRT为60 min,固液比为0.6,进水pH值为2,气水比为15:1;Fenton试剂最佳条件:反应时间为20 min、pH值为4.5、m(H2O2):m(COD)为2.5、n(H2O2):n(Fe2+)为6,硝基苯和COD总去除率可分别达到97.6%和68.3%。处理后的废水可生化性提高,为后续的生物处理创造了良好的条件。     

Optimization of Height of Release of Air Pollutants

A number of key projects in the Environmental Protection Agency (EPA) particulate R&;D program having applicability to industry are presented. For electrostatic precipitators (ESP) there is presented the result of work on large diameter discharge electrodes which provide a decrease in penetration of up to a factor of 4 when compared to conventional small diameter electrodes. Also discussed is the multistage ESP which provides a collection efficiency that would require a collecting plate area 4 or 5 times larger with conventional ESP technology. The E-SOX technology makes use of the multistage concept to free up space in the ESP for SO₂ removals of up to 90%. Electrostatically augmented fabric filtration provides a reduction in pressure drop of about 5 0% as compared to conventional fabric filtration. Wind tunnel modeling of windbreaks for material storage piles indicates a potential for providing engineering design data that would allow significant emission reduction caused by wind erosion     

Investigation of the characteristics of the reflectivity of clouds

This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).     

实验室质量管理体系内部审核的实施

在实施ISO／IEC17025：1999标准《检测和校准实验室能力的通用要求》过程中，通过实验室质量管理体系内部审核的实践与系统分析，识别出内部审核实施阶段的关键环节，提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法，对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。     

Estimation of uncertainty of sampling for analysis of pesticide residues

Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.     

扬中生态环境建设的思考与实践

结合扬中生态环境的基本情况和存在的不足，进行了具体分析，对扬中未来生态建设的发展方向提出了建议及实施措施。     

An application of the theory of kinematics of mixing to the study of tropospheric dispersion

The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.     

次氯酸钠发生器的研制

介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠     

Comparison of methods for evaluation of activity of photocatalytic films

Objective

This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase.

Method

The photocatalytic TiO₂ coatings included in this investigation ranged from thin commercially available coatings (Activ^TM and BioClean^TM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol?Cgel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably.

Results

The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably.

Conclusion

The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films.     

Impact of overexploitation of shellfish: northeastern coast of India

India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods.