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161.
162.
S.N. Wang P. Xu H.Z. Tang J. Meng X.L. Liu J. Huang H. Chen Y. Du H.D. Blankespoor 《Biotechnology letters》2005,26(19):1493-1496
A Pseudomonas sp. grew with nicotine optimally 3 g l–1 and at 30 °C and pH 7. Nicotine was fully degraded within 10 h. The resting cells degraded nicotine in tobacco solid waste completely within 6 h in 0.02 m sodium phosphate buffer (pH 7) at maximally 56 mg nicotine h–1 g dry cell–1. 相似文献
163.
164.
The objective of the experiment was to use starch processing waste as an alternative growth medium for cultivation of mycelia of the mushroom Phellinus linteus and to find an optimum condition under solid-state cultivation. Response surface analysis along with a central composite design was successfully applied to approximate the simultaneous effects of the substrate concentration (16-36 g l(-1)), pH (4.5-6.5), and temperature (25-35 degrees C) on the mycelial growth rate. In the model, pH and temperature significantly affected the mycelial growth but substrate concentration did not. The optimal substrate concentration, pH, and temperature for maximizing growth rate of P. linteus mycelia were found to be 16.5 g l(-1), pH 6.0, and 29.7 degrees C, respectively. Subsequent verification of these levels agreed with model predictions and the maximum mycelial growth rate at these conditions was 6.1 +/- 0.8 mm day(-1). Therefore, the results of the experiments suggest that starch processing waste could be utilized as a growth substrate for the cultivation of the mushroom mycelia of P. linteus, enhancing the usefulness of this byproduct of the starch manufacturing industry. This approach is likely to be useful for establishing similar parameters for the cultivation of other fungi. 相似文献
165.
Copepods and branchiopods of temporary ponds in the Doñana Natural Area (SW Spain): a four-decade record (1964–2007) 总被引:1,自引:1,他引:0
The Doñana Natural Area includes a large array of wetlands with the highest degree of environmental protection in Spain, and so it has long attracted many studies. We present a cumulative list of zooplankton taxa (Copepods and Branchiopods) based on a collection of 18 publications (1964–2007) and 4 unpublished studies. Seventy-eight taxa have been recorded in a set of 55 ponds, and 72 taxa at 38 sites spread over the Doñana marshland. In total, 96 taxa have been recorded, including 50% of all branchiopod species reported for the whole Iberian Peninsula. Taxa composition was significantly segregated between ponds and marshland during floods (ANOSIM test, R = 0.929, P < 0.01), but this segregation disappeared at a larger spatio-temporal scale when a non-metric MDS ordination produced a gradient from ponds to marshland (ANOSIM test, R = 0.272, P < 0.01). The lack of segregation between ponds and marshland sites, and among ponds with different hydroperiods, was not due to a large number of cosmopolitan species, but to a random distribution of a large number of low-occurrence species (67% of total taxa occurred with a frequency <15%). Long-hydroperiod ponds occupy a key position among the Doñana wetlands in terms of biodiversity as these ponds accumulated a high crustacean richness over time. They also supported a significantly higher cumulative number of cladoceran and harpacticoid taxa, while short-hydroperiod ponds accumulated the lowest number of diaptomid taxa. Our data indicate the need for recording biodiversity in the long term as richness on a short-temporal scale is not a good indicator of the number of crustacean species that would be encountered with a longer sampling period in Mediterranean temporary wetlands. 相似文献
166.
Xian Qu Laurent Mazéas Vasily A. Vavilin Jonathan Epissard Mélanie Lemunier Jean-Marie Mouchel Pin-jing He & Théodore Bouchez 《FEMS microbiology ecology》2009,68(2):236-245
Reconstituted municipal solid waste (MSW) with varying contents of putrescible and cellulosic waste was incubated anaerobically under mesophilic conditions. Standard physicochemical parameters were monitored, together with stable isotopic signatures of produced CH4 and CO2 . δ13 C values for CH4 indicated a change of methanogenic metabolism with time. CH4 was predominantly produced from H2 /CO2 at the beginning of the incubations. This period was associated with important shifts in archaeal communities monitored by automated ribosomal intergenic spacer analysis (ARISA) and FISH of oligonucleotidic probes targeting specifically 16S rRNA gene of various methanogenic groups. The onset of the active methane generation phase was characterized by an increase of CH4 δ13 C, indicating a progressive shift toward an aceticlastic metabolism. When the methane production levelled off, a decrease in the isotopic signature was observed toward values characteristics of hydrogenotrophic metabolism. ARISA profiles were, however, found to be stable from the beginning of the active methane generation phase until the end of the experiment. FISH observation indicated that members of the family Methanosarcinaceae were predominant in the archaeal community during this period, suggesting that these methanogens might exhibit a high metabolic versatility during methanization of waste. 相似文献
167.
Lucia Rigamonti Mario Grosso Maria Caterina Sunseri 《The International Journal of Life Cycle Assessment》2009,14(5):411-419
Background, aim, and scope Life cycle assessment (LCA) applied to alternative waste management strategies is becoming a commonly utilised tool for decision
makers. This LCA study analyses together material and energy recovery within integrated municipal solid waste (MSW) management
systems, i.e. the recovery of materials separated with the source-separated collection of MSW and the energy recovery from
the residual waste. The final aim is to assess the energetic and environmental performance of the entire MSW management system
and, in particular, to evaluate the influence of different assumptions about recycling on the LCA results.
Materials and methods The analysis uses the method of LCA and, thus, takes into account that any recycling activity influences the environment not
only by consuming resources and releasing emissions and waste streams but also by replacing conventional products from primary
production. Different assumptions about the selection efficiencies of the collected materials and about the quantity of virgin
material substituted by the reprocessed material were made. Moreover, the analysis considers that the energy recovered from
the residual waste displaces the same quantity of energy produced in conventional power plants and boilers fuelled with fossil
fuels.
Results The analysis shows, in the expanded model of the material and energy recovering chain, that the environmental gains are higher
than the environmental impacts. However, when we reduce the selection efficiencies by 15%, the impact indicators worsen by
a percentage included between 10% and 26%. This phenomenon is even more evident when we consider a substitution ratio of 1:<1
for paper and plastic: The worsening is around 15–20% for all the impact indicators except for the global warming for which
the worsening is up to 45%.
Discussion Hypotheses about the selection efficiencies of the source-separated collected materials and about the substitution ratio have
a great influence on the LCA results. Consequently, policy makers have to be aware of the fact that the impacts of an integrated
MSW management system are highly dependent on the assumptions made in the modelling of the material recovery, as well as in
the modelling of the energy recovery.
Conclusions LCA allows to evaluate the impacts of integrated systems and how these impacts change when the assumptions made during the
modelling of the different single parts of the system are modified. Due to the significant impacts that hypotheses about material
recovery have in the results, they should be expressed in a very transparent way in the report of LCA studies, together with
the assumptions made about energy recovery.
Recommendations and perspectives The results suggest that the hypotheses about the value of the substitution ratio are very important, and the case of wood
should therefore be better analysed and a substitution ratio of 1:<1 should be used, as for paper and plastic. It seems that
the assumptions made about which material is replaced by the recycled one are very important too, and in this sense, more
research is needed about what the recycled plastic may effectively substitute, in particular the polyolefin mix. 相似文献
168.
Biodrying for mechanical–biological treatment of wastes: A review of process science and engineering
C.A. Velis P.J. LonghurstG.H. Drew R. SmithS.J.T. Pollard 《Bioresource technology》2009,100(11):2747-2761
Biodrying is a variation of aerobic decomposition, used within mechanical–biological treatment (MBT) plants to dry and partially stabilise residual municipal waste. Biodrying MBT plants can produce a high quality solid recovered fuel (SRF), high in biomass content. Here, process objectives, operating principles, reactor designs, parameters for process monitoring and control, and their effect on biodried output quality are critically examined. Within the biodrying reactors, waste is dried by air convection, the necessary heat provided by exothermic decomposition of the readily decomposable waste fraction. Biodrying is distinct from composting in attempting to dry and preserve most of biomass content of the waste matrix, rather than fully stabilise it. Commercial process cycles are completed within 7–15 days, with mostly H2O(g) and CO2 loses of ca. 25–30% w/w, leading to moisture contents of <20% w/w. High airflow rate and dehumidifying of re-circulated process air provides for effective drying. We anticipate this review will be of value to MBT process operators, regulators and end-users of SRF. 相似文献
169.
The biological stabilisation of the organic fraction of municipal solid waste (OFMSW) into a form stable enough for land application can be achieved via aerobic or anaerobic treatments. To investigate the rates of degradation (e.g. via electron equivalents removed, or via carbon emitted) of aerobic and anaerobic treatment, OFMSW samples were exposed to computer controlled laboratory-scale aerobic (static in-vessel composting), and anaerobic (thermophilic anaerobic digestion with liquor recycle) treatment individually and in combination. A comparison of the degradation rates, based on electron flow revealed that provided a suitable inoculum was used, anaerobic digestion was the faster of the two waste conversion process. In addition to faster maximum substrate oxidation rates, anaerobic digestion (followed by post-treatment aerobic maturation), when compared to static composting alone, converted a larger fraction of the organics to gaseous end-products (CO2 and CH4), leading to improved end-product stability and maturity, as measured by compost self-heating and root elongation tests, respectively. While not comparable to windrow and other mixed, highly aerated compost systems, our results show that in the thermophilic, in-vessel treatment investigated here, the inclusion of a anaerobic phase, rather than using composting alone, improved hydrolysis rates as well as oxidation rates and product stability. The combination of the two methods, as used in the DiCOM® process, was also tested allowing heat generation to thermophilic operating temperature, biogas recovery and a low odour stable end-product within 19 days of operation. 相似文献
170.
Ying Xiong Chaitanya Raj Adhikari Hidetaka Kawakita Keisuke Ohto Katsutoshi Inoue Hiroyuki Harada 《Bioresource technology》2009,100(18):4083-4089
Persimmon waste was chemically modified with dimethylamine (DMA) to obtain a tertiary-amine-type gel, named DMA persimmon waste gel (DMA-PW). It was found to be effective for the adsorption of Au(III), Pd(II), and Pt(IV) in hydrochloric acid medium. In contrast, base metals such as Cu(II), Zn(II), Fe(III), and Ni(II) were not practically adsorbed. The formation of ion pairs of the metal chloro complex anions with the protonated adsorption gels was proposed as the main adsorption process. The gel exhibited selectivity only for precious metals with a remarkably high capacity for Au(III), i.e., 5.63 mol/kg dry gel and comparable capacities, i.e., 0.42 and 0.28 mol/kg for Pd(II) and Pt(IV), respectively. According to the kinetic and electrochemical studies, the adsorption rate of Au(III) was greatly enhanced by the chemical modification. Also, its excellent adsorption characteristics for the precious metals were confirmed by adsorption and elution tests using a column packed with the DMA-PW gel. 相似文献