《人造生物膜》对制药废水污染的水体生态修复效果

DMZ水塘长期接纳某制药厂排入的废水,塘中积累了大量的抗菌物质和污染物,虽曾采取多种治理措施,但因对微生物制剂具有很强的抑制作用,使其不能发挥净化作用。经应用《人造生物膜》进行治理,试验结果表明,却大幅度降低了该污染水体中的COD、NH3-N、臭气,提高了透明度,使一池死水重现生机,因此,对《人造生物膜》中应用的菌株保护作用及其生态修复效果作了分析探讨。     

除藻剂应急治理玄武湖蓝藻水华实验研究

湖泊富营养化是中国目前及今后相当长一段时期内的重大水环境问题,研究蓝藻水华治理的关键技术具有重要的生态和环境意义.2005年9月在南京玄武湖开展了化学除藻剂治理蓝藻水华的实验研究,除藻剂平均用量为26.87 g/m2,治理后实验区藻类总量下降了82.8%;水体各项理化指标得到一定改善,但停止洒药后部分指标回升;浮游动物未出现显著变化.实验结果表明,除藻剂可能在短时间内除抑蓝藻,但不能从根本上解决湖泊富营养化问题.     

北京南海子湖藻垫在春夏交替季节水华过程中的作用

藻垫对湖泊水体水华发生是否有影响及影响机制是目前水体富营养化研究的一个前沿课题。本文以北京南海子湖为例,研究湖底藻垫对水体水华爆发的影响。通过对干燥藻垫和水华过程新产生的藻垫进行培养对比实验,揭示不同时期形成的藻垫对水体藻生物量的影响即水华的影响。结果表明,不同干燥时间的藻垫均对水体藻生物量有影响,进入藻生长平台期,水体叶绿素a浓度范围为15~20 μg/L,而灭菌后的藻垫培养水体中叶绿素a浓度低于10 μg/L;水华爆发后新生成的藻垫对水体藻生物量也有贡献,培养水体叶绿素a范围也达到15-20 μg/L;干燥时间对藻垫培养后水体浮游植物生物量的影响较弱。     

中国首艘超声除藻船在常州下水

由多家企业、科研单位联合研制的我国第一艘具有完全自主知识产权的超声除藻船舶“大友之星01号”日前在常州正式下水启用,将为规模化治理蓝藻提供新的途径。这种超声除藻船舶采用了低功率（0．5～50．0w）“超声空化除藻”这一具有自主知识产权的新技术,可在30～600s内,以低功率超声辐射破坏藻细胞内的气泡,使藻细胞生物活性消失,降低水体中藻细胞的浓度,同时不会导致藻细胞粉碎性破坏而释放毒素。     

某水源水库嗅味来源及潜在产嗅藻分布特征解析

华东地区某水源水库近年来出现季节性嗅味问题。为解析嗅味产生来源及其成因,于2018年4月至2019年12月对该水库上游以及库内水体进行长期监测。监测结果表明,2-甲基异莰醇(2-MIB)是主要的土霉味致嗅物质,伪鱼腥藻是该水库潜在产嗅藻种,且其主要为外源输入。相关性分析结果表明,伪鱼腥藻的生长与水温及水下光照(透明度、浊度)等有关。为进一步解析水下光照因素驱动下伪鱼腥藻在水库水体中的分布特征,在水库高嗅期间开展了72 h连续监测,重点分析了伪鱼腥藻昼夜与垂向分布特征。结果表明,在08:00,伪鱼腥藻往表层迁移,在10:00—14:00,表层密度达到最高值,白天在水体中呈现明显的垂向迁移特征,而夜晚在水体中各层的分布无明显变化,这进一步说明水下光照对伪鱼腥藻生长的重要性。以上结果进一步提升了对实际水体中伪鱼腥藻分布规律的认识,可为水源地中伪鱼腥藻导致的嗅味问题提供借鉴。     

壳聚糖-镧改性膨润土的制备及除藻除磷性能

为解决对于富营养化水体同步进行除藻、除磷的问题,采用膨润土作为基质材料,通过壳聚糖和镧进行复合改性处理,制备了壳聚糖-镧复合改性膨润土(CLMB),考察了CLMB的除藻除磷性能及相关的影响因素,并将CLMB用于富营养化水体修复研究。结果表明：制备的CLMB在投加量为50 mg·L⁻¹时,叶绿素a(Chl-a)和浊度去除率分别为95.63%和92.55%;CLMB在pH为4~8及淡水环境下除藻效率较高;CLMB对磷的吸附更适合Langmuir方程和准二级动力学模型,在35 ℃时CLMB对磷的饱和吸附量达到13.46 mg·g⁻¹。CLMB用于富营养化水体修复的结果表明,CLMB具有快速絮凝除藻作用,富营养化水体从修复前的重度富营养化改善至中营养水平,沉水植被得到有效恢复。     

固载型TiO2光催化反应器对富营养水体杀藻作用研究

以泡沫镍作为载体,利用电沉积技术将纳米TiO2负载在泡沫镍上,制成固载型TiO2光催化反应器。研究表明,经过光催化反应器处理的富营养水体,30 h内叶绿素a由96.2 mg/m3降至2.2mg/m3,下降率达97.6％,而未负载纳米TiO2普通泡沫镍材料,在同样光强的紫外灯照射下,叶绿素a下降率为74.3％,表明紫外光照射虽然也具有一定的杀藻功能,但是光催化反应才是藻类被杀灭的主要原因。利用9.54 m3景观喷水池进行杀藻中试,光催化反应器也同样表现出优异的杀藻性能,12 d内叶绿素a由18.7 mg/m3降至1.9mg/m3,下降率达到89.8％,水体由浓绿变为清澈见底,这表明光催化反应器具有很强的杀藻能力,通过有效杀灭富营养水体中藻类、控制藻类基数,对应急处理城市景观水、湖泊等富营养水体和突发性藻华,提高生物-生态法处理效率,改善城市水环境具有十分重要的意义。     

最大光能转化效率FV/FM用于城市人工水体藻华的监控预警

结合2012年5—10月对上海市区2个典型城市人工水体藻华过程叶绿素、最大光能转化效率FV/FM变化,及其与水质指标的关系,研究FV/FM用作城市人工水体藻华监控预警指标的可行性。结果表明,曲阳公园、黄兴公园的FV/FM分别在0.57~0.71和0.58~0.63之间;人工模拟昼夜日照和温度变化培养曲阳公园藻华的水藻得到,藻类生长适应期FV/FMFV/FM>0.60,FV/FM与藻类生物量无显著相关性,仅反映藻类所处生长阶段。分析FV/FM和叶绿素a与浊度、COD、TN、TP的相关性得到,FV/FM能兼顾藻类在富营养化水体中的生理环境和生长特性,综合反映了藻华在城市人工水体形成相关的物理、化学、生长特性等因素,对研究水体FV/FM=0.63可作为预警水体藻华发生的阈值。研究成果为城市人工水体藻华暴发的监控、预警提供新的途径和方法。     

人造生物膜的脱氮作用

人造生物膜是模拟天然生物膜的新技术产品。它在污水处理中的应用已显示了高效、长效和稳定性。文中报道了用异养细菌制备的人造生物膜与硝化细菌在高分子载体上形成的生物膜组成的净化系统脱氮的试验结果。发现在好氧条件下,将加入系统中的氨氮和硝态氮几乎完全去除,表明人造生物膜具有很高的反硝化效率,并对其脱氮的机理作了讨论。     

含藻水臭氧化过程中藻内含物转化及树脂吸附净化

随着我国许多湖泊、水库等水体富营养化加重且暴发季节性蓝藻水华,饮用水安全受到极大威胁。为实现含藻水的深度净化,本研究对不同藻含量水样进行臭氧化处理,考察了氧化过程中藻内含物的释放和转化规律,对溶解性有机碳(DOC)、叶绿素a(Chl-a)、${{\rm{NH}}_4^{+} }$-N、${{\rm{NO}}_3^{-}} $-N、总氮(TN)、总磷(TP)及微囊藻毒素(MC-LR)等水质参数的动态变化进行了分析。针对氧化出水DOC和${{\rm{NO}}_3^{-}} $-N含量高的特征,选取商业化的A520和磁性MIEX树脂进行了深度吸附处理。结果表明：随臭氧化时间的延长,颗粒态藻细胞内含物逐渐变为溶解态并被氧化降解。对于高藻含量水样,氧化过程中${{\rm{NH}}_4^{+}} $-N迅速积累,有机氮主要转化为${{\rm{NH}}_4^{+}} $-N;而对于低藻含量水样,有机氮及${{\rm{NH}}_4^{+}} $-N迅速转化为${{\rm{NO}}_3^{-}} $-N,最终${{\rm{NH}}_4^{+}} $-N对TN的占比低于10%。臭氧化过程中,MC-LR质量浓度表现出先升高后降低的趋势,未被氧化降解的MC-LR可被2种阴离子交换树脂有效吸附去除,同时树脂吸附处理可显著降低水体的DOC和${{\rm{NO}}_3^{-} }$-N含量。因此,臭氧氧化耦合阴离子交换树脂吸附可实现含藻水样的深度净化,为含藻水应急处理提供了新思路。     

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.