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1.
Francisco M. Baena-Moreno Mónica Rodríguez-Galán Fernando Vega Luis F. Vilches Benito Navarrete 《International Journal of Green Energy》2019,16(5):401-412
Biomethane production through biogas upgrading is a promising renewable energy for some industries which could be part of the equilibrium needed with fossil fuels consumption to achieve a sustainable society. This paper presents a comprehensive list of biogas upgrading technologies focused on carbon dioxide removal as well as recent advances reported by researcher with wide expertise in this topic. Additionally, an extensive costs–performance comparison among the technologies studied is discussed. Among the different alternatives, chemical scrubbing stood out to achieve high biomethane purities while cryogenic technologies proved to be effective against methane losses. Regarding the different costs, water scrubbing and membrane separation seem to be the most affordable techniques. 相似文献
2.
S. S. S. Sarma Saúl Avelino Rivera Fabiola Elizalde Hinojosa S. Nandini 《Russian Journal of Ecology》2007,38(5):353-362
We tested separately the effect of two taxonomically related rotifers (B. patulus and B. macracanthus) on the population dynamics of another species (A. fissa) at low (0.5 ×10 6) and high food levels (1.5 × 106 cells/ml of Chlorella vulgaris) using different inoculation densities (0–100%). We also quantified the impact of A. fissa on the two brachionid species. Regardless of the presence of the competing species, an increase in the availability of food
led to increase in the abundances of the three rotifers. The population growth of B. patulus, B. macracanthus, or A. fissa was affected negatively when cultured together with another species. An increase in the initial density of any one of the
competing species became advantageous to maintain a certain population size. At a low algal food level, B. patulus was able to suppress A. fissa more strongly than B. macracanthus. On the other hand, at a high food level, B. macracanthus suppressed the population of A. fissa more strongly than B. patulus. Peak population densities for A. fissa varied from about 150 to 1000 ind./ml, depending on food density and the presence of competitors. The rate of population
increase (r) of A. fissa, B. patulus, and B. macracanthus increased with an increase in food availability but decreased with increasing initial density of the competitor. Both Brachionus spp. experienced negative growth rates in the presence of A. fissa, especially at a high initial density of the latter.
Published in Russian in Ekologiya, 2007, Vol. 38, No. 5, pp. 381–390.
The article was submitted by the authors in English. 相似文献
3.
Information technologies and the sharing of disaster knowledge: the critical role of professional culture 总被引:3,自引:0,他引:3
Marincioni F 《Disasters》2007,31(4):459-476
A comparative survey of a diverse sample of 96 US and Italian emergency management agencies shows that the diffusion of new information technologies (IT) has transformed disaster communications. Although these technologies permit access to and the dissemination of massive amounts of disaster information with unprecedented speed and efficiency, barriers rooted in the various professional cultures still hinder the sharing of disaster knowledge. To be effective the available IT must be attuned to the unique settings and professional cultures of the local emergency management communities. Findings show that available technology, context, professional culture and interaction are key factors that affect the knowledge transfer process. Cultural filters appear to influence emergency managers' perceptions of their own professional roles, their vision of the applicability of technology to social issues, and their perspective on the transferability of disaster knowledge. Four cultural approaches to the application of IT to disaster communications are defined: technocentric; geographic,; anthropocentric; and ecocentric. 相似文献
4.
Summary
Ips duplicatus withI. typographus co-inhabiting Norway spruce (Picea abies (L.) Karst.) would benefit from a pheromone blend distinct from that of the larger competitorI. typographus. GC-MS analysis showed thatI. duplicatus males feeding in the host produced ipsdienol (Id),cis-verbenol (cV),trans-verbenol (tV), myrtenol (Mt), andE-myrcenol (EM) and traces of 2-methyl-3-buten-2-ol (MB).I. duplicatus produced Id in approximately racemic form (48.9-54.5% (+)-(S)-isomer). The amounts of Id and EM released over a 9 day period had a maximum of 250 and 5 ng/h/male, respectively, on day 2. Exposure ofI. duplicatus males to myrcene and -pinene resulted in the production of small amounts of Id, cV, tV, Mt, andtrans-pinocarveol, but not of EM. In laboratory bioassays with walking beetles, the pheromone component Id alone was weakly attractive while EM was inactive, but in binary combination with Id strongly synergized attraction. A combination of EM and Id at a release rate equivalent to 100–200 males was more attractive in the field than 70 unmated males in a spruce log. The addition of myrcene ( a suggested pheromone precursor of Id) to Id did not enhance trap caches, while addition of EM increased catches > 10-fold. Subtracting EM from a blend of Id, EM, cV and MB drastically reduced trap catches while subtraction of cV or MB or both had no significant effect. Addition of EM over a wide concentration range to the synthetic pheromone ofI. typographus did not reduce the attraction of females of this species in the laboratory. A two-species pheromone interaction field test releasingI. typographus pheromone components (MB + cV) at 10–1000 male equivalents (ME) andI. duplicatus pheromone (Id + EM) at 0, 10–1000 ME in all possible combinations showed both positive intraspecific dose-response effects and an interspecific inhibition. Higher release rates of EM appeared to inhibitI. typographus, especially males. In a tree colonization model, the response of the two competing species to their respective pheromones show a good separation during the mass-attack with a small initial cross-attraction. It remains to be shown whether either of the two pheromone systems have in fact evolved in the present sympatry, or if they are an incidental effect of ancestry of these phylogenetically distantIps. 相似文献
5.
介绍了我国模具工业结构现状及敏捷制造的基本思想 ,论述了应用敏捷制造建立模具行业的动态联盟可缩短模具设计和制造周期 ,提高我国模具工业的竞争力。 相似文献
6.
Eco-environmentalinformationsystemofTianjinCity─Design,implementationandapplicationsHuXiaolin;YangBangjie;ZongYaoguang;LuLi(R... 相似文献
7.
8.
A study on root competition in alley cropping was carried out in an agroforestry system, involving Cassia siamea Lam. and maize ( Zea mays L. cv. Katumani composite B). The existence and intensity of root competition in the top soil as manifested by the distribution of the active roots of cassia and maize, in space and time, was assessed. The root length density of maize was far greater than that of cassia in the upper 10 cm, implying that cassia was not competing with maize for water and/or nutrients at that depth. However, at maize crop tasselling and grain filling stages there was a marked overlap of roots of the two plants at lower depths (20—50 cm). This varied with distance from the cassia hedge in a way that there was a tendency for highest overlap near middle maize rows. This partly explained observed yield differences. Therefore cassia may not be a suitable choice for alley cropping with maize under semi-arid conditions on non-sloping land, unless most of its active roots can be properly managed to absorb resources below the feeding rhizosphere of the active maize roots. 相似文献
9.
Herlander Mata‐Lima A. Alvino‐Borba Ivan Y. Salazar Vasquez Jakelline Jard da Silva Bruno Hernandez Incau José A. Almeida 《环境质量管理》2017,27(1):41-48
In view of the Brazilian Ten‐Year Energy Expansion Plan 2021, this article presents a discussion on environmental flow (e‐flow). The authors analyze the literature to show the evolution of publications concerning e‐flow releases from the perspective of ecosystems services preservation considering results from different case studies from throughout the world. Finally, two main recommendations are drawn regarding e‐flow are: (1) performing a holistic approach to e‐flow planning, including hydrological, hydraulic, water quality, habitat, and riparian zone considerations; and (2) installing in new structures adequate bottom outlets to allow a range of adjustable e‐flow from reservoir dams to reproduce natural flow variations. 相似文献
10.
Gunnar Cerwén Carola Wingren Mattias Qviström 《Journal of Environmental Planning and Management》2017,60(7):1253-1275
While soundscape is increasingly acknowledged within landscape planning and design discourse, there is little research that clarifies how soundscapes are actually dealt with in landscape architecture practice – partly owing to methodological insufficiencies. This paper, therefore, describes a model for evaluating soundscape treatment in landscape design proposals, focusing on three key aspects. With the dual aim of testing the model, and learning more about how soundscape is approached in practice, the paper spotlights a major design competition for a new cemetery in Sweden. The model proved fruitful and easy to apply. It showed that only limited attention was paid to soundscape in the competition as a whole, and was a useful means of pinpointing proposals where soundscape was fully considered as a design feature; one competition entry that did so is described in the paper. Discussions cover design practice, trends in the competition and model application. 相似文献