聚糖菌颗粒污泥的有机物吸收及胞内储存特性

采用特殊运行方式的厌氧-好氧SBR系统(厌氧后排水),在乙酸钠、葡萄糖及葡萄糖-乙酸钠混合基质条件下均培养出了稳定的聚糖菌颗粒污泥.通过对典型周期有机物、磷酸盐、胞内糖原及聚β-羟基丁酸(PHB)变化的测定分析,证明有机基质的种类对于聚糖菌能量利用模式、有机物吸收速率及胞内储存物质种类具有显著的影响.污泥初始胞内糖原水平是有机物吸收数量及吸收速率的关键影响因素,当糖原水平低于0.05g/gSS时,厌氧有机物去除率与糖原水平直接相关:而糖原水平高于0.05g/gSS时,厌氧有机物去除率趋于稳定.不同糖原水平污泥厌氧吸收有机物的速率具有明显差异,在厌氧初期有机物快速吸收阶段,有机物厌氧吸收速率随胞内糖原水平升高而增加.     

F/M对ASBR中基质的吸收、储存和利用影响

研究了不同F/M（COD/VSS）下以葡萄糖为基质时厌氧序批式反应器（ASBR）中的微生物代谢规律.结果表明,在序批操作条件下,水解产酸菌对葡萄糖的代谢存在2条并列的途径,即直接代谢为VFA和首先转化为胞内储存物糖原,然后糖原再被转化为VFA.前者约占进水COD的34%～38%,而后者则高达41%～46%.F/M越高,糖原的储存量越大,当F/M分别为0.27、 0.20和0.14时,单位质量污泥糖原的最大储存量分别为116.8、 81.1和62.4 mg/g.糖原的储存减缓了VFA的积累,为ASBR反应器的高效和正常运行创造了条件.     

单级好氧除磷工艺与厌氧/好氧除磷工艺的对比研究

以A/O工艺和单级好氧除磷工艺为研究对象,利用生活污水中存在最广泛的乙酸钠作为单一碳源,对比研究了2组SBR（A/O工艺,SBR1;单级好氧除磷工艺,SBR2）的除磷效果.连续进行3个月的研究表明,2组SBR在稳定除磷阶段的除磷率和单位污泥的除磷水平分别为91.72%和3.23 mg.g-1（SBR1）与71.70%和2.91 mg.g-1（SBR2）.进一步研究还发现：在SBR1中PHA合成的同时伴随着糖原质的消耗,而在SBR2中PHA合成的同时伴随糖原质的积累,这意味着单级好氧除磷工艺中PHA的合成无需糖原质的参与;在静置阶段,2组SBR都表现出了很明显的释磷现象,但SBR2具有更高的释磷水平（释磷量分别为2.6 mg.L-1和13.28 mg.L-1）.SBR1和SBR2体现出不同的除磷能力的原因很有可能是2组SBR的微生物在代谢过程中储能物质在消耗和存贮的循环过程中存在差异.     

溶解氧对活性污泥胞内贮存物和除磷性能的影响

分别以乙酸钠和葡萄糖为碳源,通过间歇实验,考察不同溶解氧(DO)浓度对厌氧-缺氧-好氧序批式反应器中活性污泥胞内贮存物聚羟基烷酸酯(PHA)、糖原和系统除磷性能的影响。实验表明:DO对以乙酸钠为碳源培养的胞内贮存物PHA和糖原影响较大,并影响污泥的除磷性能;对以葡萄糖为碳源培养的胞内物质影响较小,可能是因为细胞内存在其他类型的胞内贮存物。     

Body mass dependence of glycogen stores in the anoxia-tolerant crucian carp (<Emphasis Type="Italic">Carassius carassius</Emphasis> L.)

Glycogen is a vital energy substrate for anaerobic organisms, and the size of glycogen stores can be a limiting factor for anoxia tolerance of animals. To this end, glycogen stores in 12 different tissues of the crucian carp (Carassius carassius L.), an anoxia-tolerant fish species, were examined. Glycogen content of different tissues was 2–10 times higher in winter (0.68–18.20% of tissue wet weight) than in summer (0.12–4.23%). In scale, bone and brain glycogen stores were strongly dependent on body mass (range between 0.6 and 785 g), small fish having significantly more glycogen than large fish (p < 0.05). In fin and skin, size dependence was evident in winter, but not in summer, while in other tissues (ventricle, atrium, intestine, liver, muscle, and spleen), no size dependence was found. The liver was much bigger in small than large fish (p < 0.001), and there was a prominent enlargement of the liver in winter irrespective of fish size. As a consequence, the whole body glycogen reserves, measured as a sum of glycogen from different tissues, varied from 6.1% of the body mass in the 1-g fish to 2.0% in the 800-g fish. Since anaerobic metabolic rate scales down with body size, the whole body glycogen reserves could provide energy for approximately 79 and 88 days of anoxia in small and large fish, respectively. There was, however, a drastic difference in tissue distribution of glycogen between large and small fish: in the small fish, the liver was the major glycogen store (68% of the stores), while in the large fish, the white myotomal muscle was the principal deposit of glycogen (57%). Since muscle glycogen is considered to be unavailable for blood glucose regulation, its usefulness in anoxia tolerance of the large crucian carp might be limited, although not excluded. Therefore, mobilization of muscle glycogen under anoxia needs to be rigorously tested.     

Integrated assessment of CCS in the German power plant sector with special emphasis on the competition with renewable energy technologies

The study presents the results of an integrated assessment of carbon capture and storage (CCS) in the power plant sector in Germany, with special emphasis on the competition with renewable energy technologies. Assessment dimensions comprise technical, economic and environmental aspects, long-term scenario analysis, the role of stakeholders and public acceptance and regulatory issues. The results lead to the overall conclusion that there might not necessarily be a need to focus additionally on CCS in the power plant sector. Even in case of ambitious climate protection targets, current energy policy priorities (expansion of renewable energies and combined heat and power plants as well as enhanced energy productivity) result in a limited demand for CCS. In case that the large energy saving potential aimed for can only partly be implemented, the rising gap in CO₂ reduction could only be closed by setting up a CCS-maximum strategy. In this case, up to 22% (41 GW) of the totally installed load in 2050 could be based on CCS. Assuming a more realistic scenario variant applying CCS to only 20 GW or lower would not be sufficient to reach the envisaged climate targets in the electricity sector. Furthermore, the growing public opposition against CO₂ storage projects appears as a key barrier, supplemented by major uncertainties concerning the estimation of storage potentials, the long-term cost development as well as the environmental burdens which abound when applying a life-cycle approach. However, recently, alternative applications are being increasingly considered?Cthat is the capture of CO₂ at industrial point sources and biomass based energy production (electricity, heat and fuels) where assessment studies for exploring the potentials, limits and requirements for commercial use are missing so far. Globally, CCS at power plants might be an important climate protection technology: coal-consuming countries such as China and India are increasingly moving centre stage into the debate. Here, similar investigations on the development and the integration of both, CCS and renewable energies, into the individual energy system structures of such countries would be reasonable.     

不同电子受体驯化聚糖菌反硝化过程及N2O释放特性

利用序批式（sequencing batch reactor,SBR）生物反应器,采用厌氧-好氧运行方式,以乙酸钠为碳源,在控制进水P/COD<2/100条件下,成功实现了聚糖菌（glycogen accumulating organisms,GAOs）富集。缺氧初始阶段ρ（NO_x--N）为30.0 mg/L,经厌氧-缺氧驯化后,反硝化聚糖菌（denitrifuing GAOs,DGAOs）可利用聚-β-羟基脂肪酸酯（poly-β-hydroxyalkanoate,PHA）为内碳源进行反硝化,且分解利用的PHA中80%以上为聚-β-羟基丁酸酯（poly-β-hydroxybutyrate,PHB）。高浓度NO₂-抑制DGAOs活性,厌氧PHA合成降低,且缺氧段PHA分解产生的能量较多地用于储存糖原（glycogen,Gly）。NO₃-和NO₂-还原过程中,PHA降解速率分别为19.28,10.02 mg/（g·h）,内源反硝化速率分别为3.32,2.29 mg/（g·h）,TN去除率达95%以上。随NO₂-/NO_x-增加,N₂O平均产率由29.1%增至59.0%。高浓度NO₂-对氧化亚氮还原酶（Nos）活性抑制作用以及Nos和亚硝态氮还原酶（Nir）之间的电子竞争过程,是导致NO₂-内源反硝化过程中N₂O大量释放的主要原因。     

Enhancement of simultaneous nitrogen and phosphorus removal using intermittent aeration mechanism

Biological nutrient removal grows into complicated scenario due to the microbial consortium shift and kinetic competition between phosphorus (P)-accumulating and nitrogen (N)-removing microorganisms. In this study, three sequential batch reactors with constant operational conditions except aeration patterns at 6 h cycle periods were tested. Intermittent aeration was applied to develop a robust nutrient removal system aimed to achieve high energy saving and removal efficiency. The results showed higher correspondence of P-uptake, polymeric substance synthesis and glycogen degradation in intermittent-aeration with longer interval periods compared to continuous-aeration. Increasing the intermittent-aeration duration from 25 to 50 min, resulted in higher process performance where the system exhibited approximately 30% higher nutrient removal. This study indicated that nutrient removal strongly depends on reaction phase configuration representing the importance of aeration pattern. The microbial community examined the variation in abundance of bacterial groups in suspended sludge, where the 50 min intermittent aeration, favored the growth of P-accumulating organisms and nitrogen removal microbial groups, indicating the complications related to nutrient removal systems. Successful intermittently aerated process with high capability of simple implementation to conventional systems by elemental retrofitting, is applicable for upgrading wastewater treatment plants. With aeration as a major operational cost, this process is a promising approach to potentially remove nutrients in high competence, in distinction to optimizing cost-efficacy of the system.     

Reducing the energy penalty of CO2 capture and compression using pinch analysis

Integration of CO₂ capture and storage (CCS) into coal-fired power stations is seen as a way of significantly reducing the carbon emissions from stationary sources. A large proportion of the estimated cost of CCS is because of the additional energy expended to capture the CO₂ and compress it for transport and storage, reducing the energy efficiency of the power plant. This study uses pinch analysis and heat integration to reduce the overall energy penalty and, therefore, the cost of implementing CCS for power plants where the additional heat and power for the CCS plant will be provided by the existing power plant. A combined pinch analysis and linear programming optimisation are applied to determine targets for the energy penalty of existing power plants. Two existing pulverised brown coal power plants with new CCS plants using solvent absorption are used as the basis for the study that show the energy penalty can be reduced by up to 50% by including effective heat integration. The energy penalty can be further reduced by pre-drying the coal.     

环糊精对硝基苯微生物降解的影响

研究了硝基苯的生物降解过程,探讨了在降解过程中加入环糊精造成的影响.结果表明,环糊精可以提高降解菌对硝基苯的耐受浓度,缩短降解菌的停滞时间,促进降解菌的生长,加快硝基苯的降解.这种作用与环糊精和硝基苯的浓度有关,硝基苯浓度高于降解菌的耐受浓度时影响更为显著;环糊精浓度越高,影响越大.     

An objective urban heat storage model and its comparison with other schemes

An objective hydteresis model to predict the storage heat flux in urban areas is presented. A review of observational and theoretical work reveals this approach to be more approproate than the linear relation between soil heat flux and net all-wave radiation. A scheme to implement the model in any urban area is developed. In essence the model only requires land cover and net all-wave radiation as input, but it can be further refined to include anthropogenic heat release, the three-dimensional form of the surface, and can allow for changes in source area. Tests against energy balance data from a site in Vancouver, BC indicate the model simulates most aspects of measured storage heat flux values for a suburban site in both winter and summer. Comparison with the results of a study in Bonn, Germany involving the use of heat flux plates and detailed heat content change calculations gives good agreement except for a phase difference of about 1 h. There is evidence to suggest that the spatial variation of intra-urban heat storage may be relatively conservative.     

Hydrogen storage and distribution systems

Hydrogen storage and transportation or distribution is closely linked together. Hydrogen can be distributed continuously in pipelines or batch wise by ships, trucks, railway or airplanes. All batch transportation requires a storage system but also pipelines can be used as pressure storage system. Hydrogen exhibits the highest heating value per weight of all chemical fuels. Furthermore, hydrogen is regenerative and environment friendly. There are two reasons why hydrogen is not the major fuel of toady’s energy consumption: First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water. This implies that we have to pay for this energy, which results in a difficult economic task, because since the industrialization we are used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is the low critical temperature of 33 K, i.e. hydrogen is a gas at room temperature. For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage system is crucial. Hydrogen can be stored by six different methods and phenomena: high pressure gas cylinders (up to 800 bar), liquid hydrogen in cryogenic tanks (at 21 K), adsorbed hydrogen on materials with a large specific surface area (at T < 100 K), absorbed on interstitial sites in a host metal (at ambient pressure and temperature), chemically bond in covalent and ionic compounds (at ambient pressure), oxidation of reactive metals e.g. Li, Na, Mg, Al, Zn with water. These metals easily react with water to the corresponding hydroxide and liberate the hydrogen from the water. Finally, the metal hydroxides can be thermally reduced to the metals in a solar furnace.     

CO2收集封存战略及其对我国远期减缓CO2排放的潜在作用

碳收集封存(CCS)已被广泛地认为是一种潜在的、可供选择的CO₂减排方案,以稳定大气中CO₂浓度、减缓气候变化.本文介绍了CCS的3大环节：碳的捕获、运输与储存,对不同捕获技术及其技术经济参数进行分析评价,介绍了不同碳地质储存的机理、潜力与成本, 以及CCS的应用对全球减缓碳排放的作用.更新中国MARKAL模型,加入各种可能的CCS技术,特别是考虑CCS的煤间接液化以及多联产技术,以同时考虑石油安全与CO₂减排.通过设置不同的情景,应用中国MARKAL模型研究了CCS对我国远期（到2050年）减缓CO₂排放的潜在作用,结果表明,CCS技术的应用不仅可能减少我国的碳排放,降低边际碳减排成本（碳减排率50%时,下降率达45%）,减轻高减排率时对核电的高度依赖,还可能使我国更长时间地清洁利用煤炭资源（在C70情景下,2050年煤在一次能源消费中的比例可从10%增到30%）.我国应重视对CCS技术的研发以及示范项目的建设.     

食管癌高发区粮食防霉实验

磁县是我国食管癌高发区,当地居民饮食中霉菌及其毒素污染严重。为了从病因水平上预防肿瘤发生,进一步探讨了磁县食管癌高发区居民饮食防霉措施。本实验研究了防腐剂富马酸二甲酯（DMF）对磁县农户正在食用的储粮的抑霉防霉及抑菌作用。结果发现DMF可明显抑制粮食中霉菌的生长。小麦洗液培养56小时后DMF处理组霉菌菌落数平均为2.3个,而对照组可达123.7个,抑制率为95.15％。在含有DMF的培养基上霉菌不能生长。此外DMF还有明显抑菌作用,加DMF后48h即可抑制细菌生长,施药处出现明显的抑菌环。因此,应在食管癌高发区对农村储粮推广使用DMF防霉措施,以期通过降低霉菌及其毒素的污染,阻断食管癌的霉菌病因,进一步降低食管癌发病率。     

半导体桥点火具药剂贮存寿命分析及评估

目的 对在贮存过程中的半导体桥火工品进行失效分析和寿命评估.方法 通过差示扫描量热法(DSC)对不同加速寿命实验时间的半导体桥点火具药剂进行分析,探究LTNR和亚铁氰化铅的药剂相容性.通过化学动力学,分析半导体桥点火具药剂在不同加速寿命实验时间的活化能.结果 LTNR和亚铁氰化铅均表现出良好的化学相容性,在短时间内不会...     

Photocatalytic energy storage ability of TiO2-WO3 composite prepared by wet-chemical technique

TiO2-WO3 hybrid photocatalysts were prepared using wet-chemical technique, and their energy storage performance was characterized by electrochemical galvanostatic method. TiO2 powder was coupled with WO3 powder, which was used as electron pool and the reductive energy could be stored in. As a result, the prepared TiO2-WO3 had good energy storage ability while pure TiO2 showed no capacity and pure WO3 showed quite low performance. The energy storage ability was affected by the crystal structure of WO3 and ca...     

Life Cycle Assessment of fossil energy use and greenhouse gas emissions in Chinese pear production

A Life Cycle Assessment (LCA) was performed to analyze environmental consequences of different pear production chains in terms of fossil energy use and greenhouse gas (GHG) emission in China. The assessment identified hotspots that contributed significantly to the environmental impacts of pear production from the cradle to the point of sale. The results showed that GHG emissions and fossil energy use varied in the different production chains because the environmental performance does not associate with the farming systems (i.e. organic vs. conventional), but is co-determined by farm topography and thus machinery use, by market demands to seasonality of products and thus the need for storage, and by local farming practices including manure management. The LCA could be used as a tool to guide selections of agricultural inputs with the aim of reducing environmental impacts. The results of the LCA analysis indicate that a list of choices are available to reduce energy use and GHG emission in the pear production chain, namely substitution of the traditional storage systems by an efficiently controlled atmosphere storage system, using manure for biogas production, conversion from the conventional farming to organic farming, and reduction of mechanical cultivation.     

Promiscuity in mice is associated with increased vaginal bacterial diversity

Differences in the number of sexual partners (i.e., mating system) have the potential to exert a strong influence on the bacterial communities present in reproductive structures like the vagina. Because this structure serves as a conduit for gametes, bacteria present there may have a pronounced, direct effect on host reproductive success. As a first step towards the identification of the relationship between sexual behavior and potentially pathogenic bacterial communities inhabiting vital reproductive structures, as well as their potential effects on fitness, I sought to quantify differences in bacterial diversity in a promiscuous and monogamous mammal species. To accomplish this, I used two sympatric species of Peromyscus rodents—Peromyscus californicus and Peromyscus maniculatus that differ with regard to the number of sexual partners per individual to test the hypothesis that bacterial diversity should be greater in the promiscuous P. maniculatus relative to the monogamous P. californicus. As predicted, phylogenetically controlled and operational taxonomic unit-based indices of bacterial diversity indicated that diversity is greater in the promiscuous species. These results provide important new insights into the effects of mating system on bacterial diversity in free-living vertebrates, and may suggest a potential cost of promiscuity.     

Prenatal diagnosis of Pompe's disease (type ii glycogenosis) in chorionic villus biopsy using maltose as a substrate

Uncultured trophoblasts obtained from chorionic villus biopsy during the gestation period of 8–12 weeks were assayed for alpha-glucosidase activity using maltose as the substrate. Only one major form of maltase activity with a pH optimum at 4.0 was demonstrated. Using this method, we performed prenatal diagnosis on three pregnancies at risk for the infantile form of type II glycogen storage disease. Two affected fetuses and one unaffected fetus were predicted and the diagnosis was subsequently confirmed. The maltose assay offered a direct, simple, and sensitive method for prenatal diagnosis of Pompe's disease in the first trimester.