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771.
Qilin Wang Jing Sun Kang Song Xu Zhou Wei Wei Dongbo Wang Guo-Jun Xie Yanyan Gong Beibei Zhou 《环境科学学报(英文版)》2018,30(5):378-386
The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate(AD) harvested from a wastewater treatment plant. The combination of zero valent iron(ZVI, 0–4.0 g/g total solids(TS)) and hydrogen peroxide(HP, 0–90 mg/g TS) under pH 3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18 mg HP/g TS and 2.0 g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP + ZVI conditioning. 相似文献
772.
Megan Dailey Alix I. Gitelman Fred L. Ramsey Steve Starcevich 《Environmental and Ecological Statistics》2007,14(1):55-68
Models for the analysis of habitat selection data incorporate covariates in an independent multinomial selections model (McCracken
et al. 1998) Ramsey and Usner 2003 and an extension of that model to include a persistence parameter (2003). In both cases,
all parameters are assumed to be fixed through time. Radio telemetry data collected for habitat selection studies typically
consist of animal relocations through time, suggesting the need for an extension to these models. We use a Bayesian approach
that allows for the habitat selection probabilities, persistence parameter, or both, to change with season. These extensions
are particularly important when movement patterns are expected to differ seasonally and/or when availabilities of habitats
change throughout the study period due to weather or migration. We implement and compare the models using radio telemetry
data for westslope cutthroat trout in two streams in eastern Oregon. 相似文献
773.
Francesca Gherardi 《Behavioral ecology and sociobiology》2006,59(4):500-510
A study was conducted to determine whether asymmetries in both resource-holding potential (RHP) and resource value (RV) influence
dominance and fighting behavior in the hermit crab Pagurus longicarpus. A total of 120 groups of three crabs were observed for 10 min in four experiments that tested all diverse combinations of
equal/different RHP (i.e. ‘body size’) and equal/different RV (i.e. ‘shell size’ and ‘shell quality’). In a fifth experiment,
dominant and subordinate individuals of the same size category (26 groups) were forced to enter shells of opposite quality
than those previously occupied, and then the behavior of the reconstituted original groups was observed for additional 10 min.
As expected, crabs in lower quality shells were more willing to initiate and to escalate fights. However, their attacks were
directed to any crab of the group, independently of the defender's shell quality, and the fight duration did not vary with
the different value of the resources at stake. This may indicate that P. longicarpus is unable to assess the quality of the shells available in its social environment but bases its tactical decisions during
fights solely on its own resource. This suggestion was confirmed by the change in the fighting behavior of crabs whose shell
quality was experimentally altered. This manipulation induced an overall increase in the intensity of aggression, drastic
modification of crab behavior, and inversion of the hierarchy even though these crabs have had previous experiences of wins/losses
and were familiar to the other members of the group. In this species, large crab size and/or the occupancy of adequate (and
oversized) shells appeared to be the most likely determinant of contest resolution. Individuals seemed to retain a memory
of the previously held resource and behaved accordingly. 相似文献
774.
Modeling joint production of wildlife and timber 总被引:2,自引:0,他引:2
Darek J. Nalle Claire A. Montgomery Jeffrey L. Arthur Stephen Polasky Nathan H. Schumaker 《Journal of Environmental Economics and Management》2004,48(3):997
Production of marketed commodities and protection of natural systems often conflict. A focus on only one goal can result in large losses in other goals and may result in inefficient and unsustainable outcomes. In this paper, we develop a method that combines economic and ecological models in a dynamic and spatial analysis to evaluate land use decisions and find cost-effective alternatives for which it is not possible to do better on one objective without harming another objective. The method is demonstrated using timber production and species conservation on a forested landscape over a 100-year planning horizon. Current land use strategies are simulated and compared with cost-effective alternatives. The approach is compared to a static reserve approach, similar to previous studies, and found to produce substantially more efficient management strategies for the case study landscape. 相似文献
775.
Baseline resource information in an easily accessible form is a vital starting point for developing coastal zone management.
On behalf of a wide-ranging group of organizations involved in the management of the U.K. maritime zone, the Joint Nature
Conservation Committee (JNCC) is compiling a series of 16 regional volumes. The volumes contain multidisciplinary coastal
zone resource information arranged in ten chapters under the general title ‘Coasts and Seas of the UK’. These volumes form
part of a series of paper and electronic publications of coastal information being produced by JNCC's Coastal Directories
Project and are designed to meet the needs of planners and all others involved in decision-making and management of the coast. 相似文献
776.
系统研究了医疗废物的产生量及其预测、收运方式、路线和处理、处置工艺的技术,对福州市中心城区医疗废物收运与处理、处置管理系统与运行机制提出建设性意见。 相似文献
777.
778.
开拓有机高分子絮凝剂在炼厂污水处理中的应用 总被引:4,自引:0,他引:4
顾薇琼 《石油化工环境保护》1997,(2):35-38
通过有机高分子絮凝剂在炼厂污水处理中的应用试验,表明有机高分子絮凝剂各方面性能均优于单一的无机盐絮凝剂。开拓有机高分子絮凝剂在炼厂污水处理中的应用,是当前提高污水外排综合合格率的一个重要手段。 相似文献
779.
用浮选法处理铵盐镀锌废水的研究 总被引:1,自引:0,他引:1
研究用浮选法除去铵盐镀锌废水中的锌.实验结果表明,用H2O2作氧化剂破坏络合物,用十二烷基磺酸钠作吸收剂,沉淀浮选法除锌是十分有效的 相似文献
780.
本文首先从实践和理论层面论证了目标意志对一个人成才和发展的重要意义。在此基础上,进一步提出了培养大学生目标意志的具体措施和途径,并结合我校学生的实际,指出了我们在培养学生的目标意志方面应转变的观念、应克服的偏见和应采取的措施。 相似文献