2种新分离微藻的生长、氮磷去除和营养特性的比较研究

为了解2种新分离微藻的净化和资源化潜力，研究比较了其生长、氮磷去除和营养特性。结果表明，栅藻和月牙藻的最大生物量（干重）分别为0．78g／L和0．53g／L；最大生物量（干重）增长速率分别为0．05g／（L·d）和0．03g／（L·d）。培养至第23天，栅藻和月牙藻对TN的去除率分别为85．1％和72．5％；对TP的去除率为82．6％和79．7％，但栅藻较月牙藻更易释放较多的No2--N进入藻液。稳定期时，栅藻、月牙藻的粗蛋白质含量和粗蛋白产量（干重）分别为31．8％、19．2％和0．24g／L、0．09g／L；粗脂含量和粗脂产量（干重）分别为7．81％、9．26％和0．06g／L、0．05g／L。综上，与月牙藻相比，栅藻具有明显的生长、氮磷去除和营养优势，在进行水产养殖废水的净化和资源化利用上可作为优选藻种。     

报废汽车再制造产业化发展浅析

以报废汽车再制造规模化、市场化、产业化发展为主线,围绕报废汽车回收拆解行业的热点问题,介绍了发达国家对报废汽车的管理模式与我国政府相关法规政策走向,分析了发展再制造产业面临的问题,以及报废汽车再制造即将朝着新兴产业化发展方向快速推进的动因和机遇。     

Integrated emergy,energy and economic evaluation of rice and vegetable production systems in alluvial paddy fields: Implications for agricultural policy in China

China is the largest rice producing and consuming country in the world, but rice production has given way to the production of vegetables during the past twenty years. The government has been trying to stop this land-use conversion and increase the area in rice-vegetable rotation. Important questions that must be answered to determine what strategy is best for society are, “What is the reason behind this conversion?”; “Which system is more productive and which is more sustainable?”; and “How can economic policy be used to adjust the pattern of farmland use to attain sustainable development?” To answer these questions, a combined evaluation of these agricultural production systems was done using emergy, energy and economic methods. An economic analysis clearly showed that the reason for this conversion was simply that the economic output/input ratio and the benefit density of the vegetable production system were greater than that of rice. However, both energy and emergy evaluations showed that long-term rice was the best choice for sustainable development, followed by rotation systems. The current price of rice is lower than the em-value of rice produced from the long-term rice system, but higher than that of rice produced from the rotation system. Scenario analysis showed that if the government increases the price of rice to the em-value of rice produced from the long-term rice system, US$0.4/kg, and takes the value of soil organic matter into account, the economic output/input ratios of both the rice and rotation systems will be higher than that of the vegetable system. The three methods, energy, emergy and economics, are different but complementary, each revealing a different aspect of the same system. Their combined use shows not only the reasons behind a system’s current state or condition, but also the way to adjust these systems to move toward more sustainable states.     

The sorption of selenite from aqueous solutions by pyrite

Selenium (Se) is an essential trace nutrient for mammals; however, the range between deficit and toxic levels is narrow. In this study, the potential sorption of selenite onto pyrite particles from an aqueous solution was investigated. An intraparticle diffusion model was used to describe kinetic data of sorption, yielding diffusivity values of 5 × 10^?7 cm²/s. The Langmuir isotherm equation could be used to describe the experimental data. The fitting results indicated that b and {Se(IV)}_max have values of 0.37 L/mg and 3.49 mg/g, respectively. The sorption of selenite onto the surface of pyrite particles was dependent on a pH range of 2–12, and the quantity of sorption onto pyrite was negatively correlated with pH; that is, the amount of sorption onto pyrite increased with a decrease in pH. In addition, organic matter did not exert a significant effect on removal of selenite. With a reaction time greater than 1 week, sorption of selenite onto pyrite particles was found to partially reduce the amount of elemental Se.     

杠板归的化学成分

采用柱层析方法从蓼科药用植物杠板归(Polygonum Perfoliatum)分离了21个化合物(1～21),通过MS与NMR数据鉴定这些化合物为α-tocopherolquinone (1), 7'-dihydroxymatairesinol (2), (24S)-24-ethylcholesta-3β,5α,6α-triol (3), 4-dihydroxy-5,7-dihydroxy-4-(4-hydroxyphenyl) coumarin (4), quercetin (5), cucurbitacin Ⅱa (6), cucurbitacin U (7), iotroridoside A (8), pokeweedcerebroside 5 (9), bonaroside (10), helonioside A (11), helonioside B (12), lapathoside D (13), vanicoside B (14), vanicoside C (15), vanicoside F (16), asteryunnanoside F (17), saikosaponin M (18), hydropiperoside (19), quercetin-3-O-β-D-glucuronide-6"-butyl ester (20), quercetin-3-O-β-D-glucuronide-6"-methyl ester (21). 化合物1～19(除4,5,12)为首次从该植物中分离得到,化合物1～11(除4,5)和17～19为首次从该属植物中分离得到.图1参22     

产业生态系统多尺度能值整合评价方法

能值分析方法为自然环境资源与人类社会、经济的统一评价提供了新的思路,但面对当今产业生态学发展的实践需求,在多尺度整合分析、动态模型构建等方面仍显薄弱,需要与经济学等其他学科相对成熟的分析方法与模型加以整合。文章以能值综合方法为核心介质,从成本分析与效果分析的整合、能值分析与区域经济分析的整合,以及能值分析表与投入-产出矩阵模型的整合三个方面进行了产业生态学的能值整合研究方法的具体构建,以促进能值理论方法与产业生态学研究需求的进一步耦合。     

锶在改性介质中的吸附规律及其影响因素研究

通过室内等温静态批量平衡吸附实验,采用2种常见的等温吸附方程(Freundlich方程、Langmuir方程)对锶在3种不同润湿性的石英砂中的吸附行为进行了回归拟合。结果表明,介质润湿性对锶的吸附会产生重要的影响,润湿性较强的亲水性石英砂的吸附性能明显优于疏水性石英砂;从Freundlich方程和Langmuir方程拟合结果来看,两者均具有理想的相关性,但普通石英砂和亲水性石英砂的等温吸附式更符合Langmuir方程,而疏水性石英砂采用Freundlich方程拟合的相关性更好。     

Vegetative Ecological Characteristics of Restored Reed (Phragmites australis) Wetlands in the Yellow River Delta, China

In this study, we compared ecological characteristics of wetland vegetation in a series of restoration projects that were carried out in the wetlands of Yellow River Delta. The investigated characteristics include plant composition structure, species diversity and community similarity in three kinds of Phragmites australis wetlands, i.e. restored P. australis wetlands (R1, R2, R3 and R4: restored in 2002, 2005, 2007 and 2009, respectively), natural P. australis wetland (N) and degraded P. australis wetland (D) to assess the process of wetlands restoration. The coverage of the R1 was 99%, which was similar to natural wetland. Among all studied wetlands, the highest and lowest stem density was observed in R1 and R2, respectively, Plant height and stem diameter show the same trend as N > R2 > R1 > R3 > D > R4. Species diversity of restored P. australis wetlands became closed to natural wetland. Both species richness and Shannon–Wiener index had similar tendency: increased first and then decreased with restored time. The highest species richness and species diversity were observed in R2, while the lowest values of those parameters were found in natural P. australis wetland. Similarity indexes between restored wetlands and natural wetland increased with the restoration time, but they were still less than 50%. The results indicate that the vegetation of P. australis wetlands has experienced a great improvement after several years’ restoration, and it is feasible to restored degraded P. australis wetlands by pouring fresh water into those wetlands in the Yellow River Delta. However, it is notable that costal degraded P. australis wetland in this region may take years to decades to reach the status of natural wetland.     

倒置A~2/O与常规A~2/O工艺除磷效果对比

通过对西安市某污水处理厂倒置A2/O工艺的沿程监测和工艺解析,分析明确了该工艺生物除磷效果差的影响因素。研究表明,缺氧池反硝化不完全,厌氧池高浓度硝酸盐是抑制聚磷菌释磷的重要因素。当厌氧池内硝酸盐浓度大于4 mg/L时会明显抑制生物除磷效果。硝酸盐的浓度在1~4 mg/L时,随着硝酸盐浓度的升高,释磷效果显著降低。为避免硝酸盐对聚磷菌的影响,需将厌氧池硝酸盐浓度控制在1 mg/L以下。硝酸盐对聚磷菌释磷的影响原因是生物脱氮除磷对碳源的竞争,以乙酸钠和原污水为碳源分析硝氮盐对释磷效果的影响。结果表明,易于生物降解的优质碳源更有利于聚磷菌在厌氧环境下释磷,倒置A2/O的前置式缺氧池首先将大量优质碳源用于反硝化,而造成后续厌氧池聚磷菌释磷效果差。针对这一研究结果,对该污水厂提出将倒置A2/O调整为常规A2/O的改造方案,改造后厌氧池硝酸盐浓度由3.57 mg/L降低至0.89 mg/L,聚磷菌释磷量提高1.8倍,系统除磷效果增强,出水总磷降低至0.66 mg/L,与倒置A2/O相比降低0.21 mg/L。