黑岱沟露天矿区排土场2种典型植物的水分来源及利用策略

论文利用稳定性同位素示踪技术,分析排土场2种典型植物水分来源的差异及水分利用策略.结果表明,黑岱沟矿区大气降水的氢,氧同位素含量均落在中国大气降水的变化范围之内,不同月份大气降水的δD(δ¹⁸Ο)值表现出明显的降水量和季节效应.旱季小叶杨主要利用10 cm土层以下的水分,对100~150 cm土层水分利用率最高,达25.6%;沙棘对各层次土壤水分的利用比例接近,差异不明显,对表层土壤水分的利用最高,达26.5%;为了避免种间竞争,小叶杨很少利用表层(0~10 cm)土壤水分.雨季小叶杨主要利用表层和浅层土壤水分,利用比例高达70.9%,沙棘主要利用30~60 cm土层的水分,达73.5%,其次是10~30 cm土层,达17.4%.两种不同生活型植物通过不同策略合理利用旱季有限的水分,而在雨季水分供给充分时,均优先利用浅层水源,使其组成的生态系统更好地适应矿区排土场脆弱的生态环境.     

燃煤电厂污染减排成本有效性分析及超低排放政策讨论

中国的空气污染与以煤为主的能源结构关系密切.燃煤电厂是中国煤炭消费量最大且大气污染物排放量最大的部门,因此,也必然成为污染物排放控制的主要对象.针对最近公布的电厂超低排放政策,本文采用成本有效性评估方法对燃煤电厂污染物减排进行了分析,研究结果表明：全面进行超低排放改造以实现污染物减排的成本高昂,其中,燃煤电厂超低排放改造的脱硫、脱硝、除尘的单位减排成本分别为：4.46万元/t,2.35万元/t,0.43万元/t.现有燃煤电厂实施超低排放的行业成本较高;鉴于其他燃煤部门技术水平相对落后、排放标准宽松,现阶段是否首先针对燃煤电厂全面实施超低排放改造需要更为全面的环境经济评估.基于本文的分析,以度电成本为衡量指标将会误导超低排放改造的减排路径选择.研究结论表明：燃煤电厂行业最低成本超低排放改造,应从规模较小、煤质水平较差的机组开始.     

The potential of current legal structures to support Aboriginal and Torres Strait Islander interests in the Australian bush food industry

There are complex connections between Australia’s native plants and first peoples, the Aboriginal and Torres Strait Islander peoples. The maintenance of these connections is central to Aboriginal and Torres Strait Islander culture and well-being and the tangible realisation of Australian policy commitments. Diverse cultural connections combine with other motivations to underpin an array of Aboriginal and Torres Strait Islander interests in the commercial development of traditional plant foods (‘bush foods’). Despite nation-wide policy support for these interests, there is no national legal framework to support them. This fortifies the popular call for a new (sui generis) law that transforms the interests of Aboriginal and Torres Strait Islander peoples into enforceable legal rights. It is unclear the extent to which a single sui generis law might help Aboriginal and Torres Strait Islander peoples realise their diverse interests in the development of gourmet bush food products and new bush food varieties. It is also unlikely that Australia will implement such a law in the near future. This paper offers a preliminary study of the capacity of current legal structures to support some key Aboriginal and Torres Strait Islander interests that might arise in these two development contexts. The study can inform the future development of practical legal strategies to support the diverse interests of Aboriginal and Torres Strait Islander peoples in the bush food industry.     

Simple model of sludge thickening process in secondary settlers

In wastewater treatment plants (WWTPs), a secondary settler acts as a clarifier, sludge thickener, and sludge storage tank during peak flows and therefore plays an important role in the performance of the activated sludge process. Sludge thickening occurs in the lower portions of secondary clarifiers during their operation. In this study, by detecting the hindered zone from the complete thickening process of activated sludge, a simple model for the sludge thickening velocity, u _s = aX ^b (a = 0.9925SSVI _3.5, b = 3.541ln(SSVI _3.5)+12.973), describing the potential and performance of activated sludge thickening in the hindered zone was developed. However, sludge thickening in the compression zone was not studied because sludge in the compression zone showed limited thickening. This empirical model was developed using batch settling data obtained from four WWTPs and validated using measured data from a fifth WWTP to better study sludge thickening. To explore different sludge settling and thickening mechanisms, the curves of sludge thickening and sludge settling were compared. Finally, it was found that several factors including temperature, stirring, initial depth, and polymer conditioning can lead to highly concentrated return sludge and biomass in a biologic reactor.     

Characterization of the genes involved in nitrogen cycling in wastewater treatment plants using DNA microarray and most probable number-PCR

To improve nitrogen removal performance of wastewater treatment plants (WWTPs), it is essential to understand the behavior of nitrogen cycling communities, which comprise various microorganisms. This study characterized the quantity and diversity of nitrogen cycling genes in various processes of municipal WWTPs by employing two molecular-based methods:most probable number-polymerase chain reaction (MPN-PCR) and DNA microarray. MPN-PCR analysis revealed that gene quantities were not statistically different among processes, suggesting that conventional activated sludge processes (CAS) are similar to nitrogen removal processes in their ability to retain an adequate population of nitrogen cycling microorganisms. Furthermore, most processes in the WWTPs that were researched shared a pattern:the nirS and the bacterial amoA genes were more abundant than the nirK and archaeal amoA genes, respectively. DNA microarray analysis revealed that several kinds of nitrification and denitrification genes were detected in both CAS and anaerobic-oxic processes (AO), whereas limited genes were detected in nitrogen removal processes. Results of this study suggest that CAS maintains a diverse community of nitrogen cycling microorganisms; moreover, the microbial communities in nitrogen removal processes may be specific.

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火电厂大气污染物排放标准对区域酸沉降影响的数值模拟

设计了火电厂实施2003版排放标准和2011版排放标准两种排放情景,运用Models-3/CMAQ模型系统分别模拟各情景到2015年的硫、氮沉降量,探讨2011版火电排放标准对我国大陆地区酸沉降的影响.研究表明,2011版火电标准能够有效改善我国的硫沉降状况,相比于实施2003版标准,2011版标准实施后至2015年我国大陆硫沉降总量降低了18.58%,年均硫沉降强度大于3.2t/km2的面积减少了86.40%;2011版火电标准对我国氮沉降状况也起到了一定的改善作用,标准实施后到2015年我国大陆氮沉降总量降低了9.28%,年均氮沉降强度大于4.0t/km2的面积减少了27.27%.     

园林植物滞留不同粒径大气颗粒物的特征及规律

为研究常用园林植物滞留大气颗粒物的能力,本文以北京市常用园林植物为例,应用直接采样、电镜分析和统计分析的方法,对选定园林植物滞留不同粒径大气颗粒物的特征及规律进行了系统分析。结果表明：（1）园林植物滞留的颗粒物形状为不规则块体、球体和聚合体,通过对比分析得出,滞留大气颗粒物能力由高到低的微形态结构依次是蜡质结构〉绒毛〉沟槽〉条状突起,并且这些微形态结构越密集、深浅差别越大,越有利于滞留大气颗粒物。（2）以园林植物叶片滞留颗粒物的数量进行统计时,得出园林植物叶片表面大部分为PM10（Dp≤10μm）,均在98%以上,而PM2.5（Dp≤2.5μm）均在90%以上,粗颗粒物（Dp〉10μm）的数量对总体数量的贡献非常小,均在2%以下;以体积进行统计时,得出PM10的体积在总体积中的比例在50%以上,对颗粒物总体积贡献最大,滞留的PM2.5体积占总体积8.5%-17.6%,粗颗粒物（Dp〉10μm）体积占总体积20%以上。（3）对园林植物滞留颗粒物累积规律分析得出：在相同观测叶面积下,园林植物滞尘10 d的叶表面颗粒物数量较滞尘5 d的叶表面颗粒物数量均有所增加,增幅最大的是小叶黄杨（Buxus microphylla）,增幅最小的是月季（Rosa chinensis）,通过方差分析得出绦柳（Salix matsudana f.pendula）叶表面颗粒物数量显著低于除银杏（Ginkgo biloba）之外的其它7种树种,大叶黄杨（Euonymus japonicus）、小叶黄杨和国槐（ Sophora japonica）叶表面滞留颗粒物的数量较多,并且显著高于月季、银杏和绦柳叶表面滞留的颗粒物数量;滞尘10 d后园林植物叶表面滞留的颗粒物的总面积均未超过观测叶面积的25%,至于叶片持续滞留颗粒物多少天后达到饱和状态仍需进一步研究。     

Modeling and optimizing efficiency gap between managers and operators in integrated resilient systems: The case of a petrochemical plant

The reliability issue in complex industrial systems such as oil, gas, petrochemical companies, nuclear and aviation industries has been of great importance. Resilience engineering (RE) is a new attitude toward the improvement of safety and reliability in the stated systems. One of the challenges a resilient system might face is the gap between work as imagined by managers and work as actually done by operators. This study will introduce a new framework named integrated resilience engineering (IRE) as a result of developing the concept of RE. The data used in this research have been obtained by means of questionnaire from a petrochemical company. Thereafter, the efficiency of operators and managers are calculated in RE and IRE frameworks through data envelopment analysis (DEA) approach. Then, the gaps between managers and operators are analyzed in two frameworks. The results are indicative of a significant growth in the number of efficient operators and managers in IRE framework compared to RE framework. Besides, the efficiency mean of managers and operators in IRE framework has experienced the growth of 1.8% and 5% compared to RE framework, respectively. The efficiency gap between managers and operators in IRE framework has also enjoyed the improvement of 88% compared to RE framework. Generally, it can be said that the suggested items of this research has led to the betterment of managers and operators’ efficiency and of the efficiency gap between them. Therefore, these items can improve the resilience and safety of complex systems. The results of Spearman test show that there is a strong direct correlation between the DEA results in two frameworks. This is the first study that examines the efficiency gap between operators and managers based on the RE principles and by means of DEA approach.     

Restoration of hyper-eutrophic water with a modularized and air adjustable constructed submerged plant bed

A modularized and air adjustable constructed submerged plant bed (CSPB) which can be used to restore the eutrophic water is introduced in this paper. This plant bed helps hydrophyte grow under poor conditions such as frequently changed water depth, impaired water transparency, algae bloom and substantial duckweed in summer, which are not naturally suitable for growing hydrophyte. This pilot study in Waihuan River of Tianjin, China, revealed that reduction of Chemical Oxygen Demand (COD), Total Nitrogen (TN) and Total Phosphorus (TP) by the use of CSPB could be reached 30%–35%, 35%–40%, 30%–40% respectively in the growing season (from March to October) and 5%–10%, 5%–15%, 7%–20% respectively in the winter (from November to February) when the detention time was 6 d. The relationships between the concentration of COD, TN, TP and the detention time fit the first-order kinetic equation well and the coefficients of determination (R²) were all above 0.9. The attenuation coefficients k of the kinetic equation were a function of the water temperature. When the water temperature was quite low or quite high, k was not significantly changed with increasing or decreasing water temperature. While when the temperature was in a moderate range, an increase or decrease of water temperature would lead to a rapid increase or decrease in k.     

Polycyclic aromatic hydrocarbons in medicinal plants from Syria

The levels of 16 US Environmental Protection Agency polycyclic aromatic hydrocarbons (EPA PAHs) in 10 medicinal plants in different used parts of plant (leaves and flowers) have been determined. The analytical method consists of sample preparation by ultrasonic extraction with dichloromethane followed by silica gel clean-up. Subsequently, the analysis was carried out by reversed-phase high-performance liquid chromatography (HPLC) coupled to both ultraviolet and fluorescence detections in series to insure the detection of all 16 EPA PAHs. It was observed that the sum of the 16 PAHs (ΣPAHs) in the investigated medicinal plants ranged from 47 to 890 μg kg^–1 where the highest ΣPAHs was found in Sage plant sample. Light PAHs were dominants in all studied medicinal plants. The sum of eight genotoxic PAHs (ΣPAH8) have shown a better indicator of the degree of contamination with carcinogenic PAHs compared to benzo[a]pyrene in these products.