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521.
This study gives a brief demonstration of impurity removal efficiency upon salt solution treatment of phosphogypsum (PG). The experimental set up has been designed according to a multi-variable Box–Behnken Design (BBD) with stirring time, solid: liquid (PG:salt solution) ratio and temperature as the conducted in various salt solutions. PG sample has been treated with sea water, 5% NaCl and 10% NaCl solutions according to the BBD matrix. Fluoride (F), copper (Cu), manganese (Mn), and nickel (Ni) amounts in the PG sample have been measured upon pre- and post-treatment with salt solutions. Among other operating conditions, temperature has been the dominant factor on fluoride removal efficiency, and responses for the factors determined in the experiment runs indicated that a significant correlation could be established between temperature and fluoride removal, sea water being the most efficient salt solution. Higher copper, manganese, and nickel removal efficiencies have been observed in single salt NaCl solution systems however no significant correlation could be established between factors. Results indicate that pre-treatment of PG located near coastal regions with sea water can be a cost-effective approach and applicable on industrial scale when fluoride removal is of importance. 相似文献
522.
Issues of connectivity between different infrastructure sectors have received surprisingly little attention in recent research. Despite huge interest in issues of sectoral integration surrounding the water–energy nexus, researchers have rarely considered what this might mean for the coupling of infrastructure systems for water/wastewater and energy services. Consequently, the implications of greater connectivity for the governance and socio-spatial constitution of infrastructures are largely unexplored. This paper addresses this research gap with a case study of an attempt to use treated wastewater to produce biomass for energy on degraded land in the Berlin–Brandenburg region of Germany. It takes water reuse for energy crop production as an exemplar of work at the water–energy nexus in order to explore the institutional, spatial and physical dimensions involved in connecting two infrastructure systems to this end. It argues that cross-sectoral integration reaches far beyond issues of technological compatibility, revealing often hidden but crucial differences in the institutional and spatial configuration of energy and wastewater systems. The paper draws conclusions on the broader implications of the case for understanding institutional challenges of cross-sectoral connectivity on the one hand and prospects for reconfiguring infrastructural relations between cities and rural areas on the other. 相似文献
523.
MATTHEW LINKIE SEAN SLOAN RAHMAD KASIA DEDY KISWAYADI WAHDI AZMI 《Conservation biology》2014,28(4):1023-1033
The government of Indonesia, which presides over 10% of the world's tropical forests, has set ambitious targets to cut its high deforestation rates through an REDD+ scheme (Reducing Emissions from Deforestation and forest Degradation). This will require strong law enforcement to succeed. Yet, strategies that have accomplished this are rare and, along with past failures, tend not to be documented. We evaluated a multistakeholder approach that seeks to tackle illegal logging in the carbon‐rich province of Aceh, Sumatra. From 2008 to 2009, Fauna & Flora International established and supported a community‐based informant network for the 738,000 ha Ulu Masen ecosystem. The network reported 190 forest offenses to local law enforcement agencies, which responded with 86 field operations that confiscated illicit vehicles, equipment, and timber, and arrested 138 illegal logging suspects. From 45 cases subsequently monitored, 64.4% proceeded to court, from which 90.0% of defendants received a prison sentence or a verbal warning for a first offense. Spatial analyses of illegal logging and timber storage incidents predicted that illegal activities would be more effectively deterred by law enforcement operations that targeted the storage sites. Although numerous clusters of incidents were identified, they were still widespread reflecting the ubiquity of illegal activities. The multistakeholder results were promising, but illegal logging still persisted at apparently similar levels at the project's end, indicating that efforts need to be further strengthened. Nevertheless, several actions contributed to the law enforcement achievements: strong political will; strong stakeholder support; and funding that could be promptly accessed. These factors are highlighted as prerequisites for achieving Indonesia's ambitious REDD+ goals. Rompiendo el Círculo Vicioso de la Tala Ilegal en Indonesia 相似文献
524.
Xiaofeng Liao Shuangyan Zhu Delai Zhong Jingping Zhu Li Liao 《Waste management (New York, N.Y.)》2014,34(11):2278-2284
In order to investigate the effect of raw leachate on anaerobic digestion of food waste, co-digestions of food waste with raw leachate were carried out. A series of single-phase batch mesophilic (35 ± 1 °C) anaerobic digestions were performed at a food waste concentration of 41.8 g VS/L. The results showed that inhibition of biogas production by volatile fatty acids (VFA) occurred without raw leachate addition. A certain amount of raw leachate in the reactors effectively relieved acidic inhibition caused by VFA accumulation, and the system maintained stable with methane yield of 369–466 mL/g VS. Total ammonia nitrogen introduced into the digestion systems with initial 2000–3000 mgNH4–N/L not only replenished nitrogen for bacterial growth, but also formed a buffer system with VFA to maintain a delicate biochemical balance between the acidogenic and methanogenic microorganisms. UV spectroscopy and fluorescence excitation–emission matrix spectroscopy data showed that food waste was completely degraded.We concluded that using raw leachate for supplement water addition and pH modifier on anaerobic digestion of food waste was effective. An appropriate fraction of leachate could stimulate methanogenic activity and enhance biogas production. 相似文献
525.
Catherine Donner MD Jean-Christophe Noel Françoise Rypens Jean van Kerkem Freddy Avni Frédéric Rodesch 《黑龙江环境通报》1995,15(1):60-63
A 29-year-old woman was referred for suspicion of twin-twin transfusion syndrome (TTTS). Several ultrasonographic and neonatal criteria of TTTS were encountered in this twin pregnancy. The peculiar observations in this case were, firstly, the demonstration of superficial anastomosis by Doppler ultrasound and, secondly, that one single therapeutic amniocentesis could have been sufficient to partially correct the progression of the syndrome, as after amniocentesis it was no longer possible to demonstrate the vascular communication. This observation suggests that superficial anastomoses could also have a role in the genesis of TTTS. Their effect could be monitored by Doppler ultrasound and could be more easily corrected by therapeutic amniocentesis. 相似文献
526.
MICHAEL A. GRAY† SANDRA L. BALDAUF† PETER J. MAYHEW† JANE K. HILL† 《Conservation biology》2007,21(1):133-141
Abstract: Anthropogenic habitat disturbance is a major threat to tropical forests and understanding the ecological consequences of this disturbance is crucial for the conservation of biodiversity. There have been many attempts to determine the ecological traits associated with bird species' vulnerability to disturbance, but no attempt has been made to synthesize these studies to show consensus. We analyzed data from 57 published studies (covering 1214 bird species) that investigated the response of tropical bird assemblages to moderate forest disturbance (e.g., selective logging). Our results show that the mean abundance of species from six commonly reported feeding guilds responded differently to disturbance and that species' ecological traits (body size, local population size, and geographic range size) and evolutionary relationships may influence responses in some guilds. Granivore abundance increased significantly and insectivore and frugivore abundance decreased significantly following disturbance. These general conclusions were robust to the effects of ecological traits and phylogeny. Responses of carnivores, nectarivores, and omnivores were less clear, but analyses that accounted for phylogeny indicated that these guilds declined following disturbance. In contrast to the other guilds, the reported responses of carnivores and nectarivores differed among regions (Asia vs. Neotropics) and were influenced by the sampling protocols used in different studies (e.g., time since disturbance), which may explain the difficulty in detecting general responses to disturbance in these guilds. Overall, general patterns governed the responses of species to habitat disturbance, and the differential responses of guilds suggested that disturbance affects trophic organization and thus ecosystem functioning. 相似文献
527.
After chorionic villus biopsy of human placenta, cell cultures were propagated with Ham's F10 medium or Eagle's minimum essential medium (MEM). It was possible to study the morphology of the cells by transmission electron microscopy (TEM) after a special culture of the cells in a collagen gel. The cells embedded in a collagen gel were able to contract the gel and to organize collagen fibres, as fibroblast cultures do. TEM showed vacuolization and well-developed cisternae of the endoplasmic reticulum, especially in the case of MEM culture. The aim was to determine whether cells cultivated from early placenta were able to synthesize enough collagen for a metabolic study. A high level of collagen biosynthesis could be quantified. Types I and III collagen can be determined which is useful for studying the abnormalities of collagen synthesis in suspected cases of osteogenesis imperfecta or Ehlers–Danlos type IV syndrome. The hydroxylation of lysine can also be studied with respect to Ehlers–Danlos type VI syndrome. Moreover, these cells, in contrast to fibroblast cultures, made it possible to study the biosynthesis of type IV collagen. 相似文献
528.
本文通过绿色植物能量转化的生理机能,即光合作用过程中太阳能的投入、转化和产出的内在联系,定量地描述了海南岛各地实际光能利用率;地区性农业生产潜力;潜在光能利用率及其与实际光能利用率的绝对差值。结果表明,全岛实际光能利用率低于全国平均水平,只及一年两熟地区的一半,高值区接近一年一熟地区;潜在光能利用率与世界热带地区差距不大;潜在与实际光能利用率之差全岛平均达5.1%,具有较大的增产潜力。文中还针对海南的实际粗略地探讨了岛内光能利用率不高的原因和提高光能利用率的相应途径。 相似文献
529.
Deficiency of amylo-1,6–glucosidase activity was expressed in parallel in liver and skin fibroblasts from a patient with type III glycogenosis. In crude extracts of control liver and muscle, amylo-1, 6–glucosidase (M.W. 164000) was identified by immunoprecipitation; no cross-reacting material was found in the patient's liver. Assay of amylo-1,6–glucosidase activity in cultured skin fibroblasts from the affected family revealed less than 10 per cent of control value in mutant homozygous cells whereas in cells from the parents, activity was reduced to 40–60 per cent of the control value. Activity in cultured amniotic fluid cells was similar to that of control fibroblasts. In cultured amniotic fluid cells obtained during the mother's subsequent pregnancy, the normal amylo–1,6–glucosidase activity measured, predicted correctly the outcome of this pregnancy prior to the 20th week of gestation. 相似文献
530.
Fabian P Kohlpaintner M Rollenbeck R 《Environmental science and pollution research international》2005,12(5):290-296
Background Biomass burning is a source of carbon, sulfur and nitrogen compounds which, along with their photochemically generated reaction
products, can be transported over very long distances, even traversing oceans. Chemical analyses of rain and fogwater samples
collected in the mountaineous rain forest of south Ecuador show frequent episodes of high sulfate and nitrate concentration,
from which annual deposition rates are derived comparable to those found in polluted central Europe. As significant anthropogenic
sources are lacking at the research site it is suspected that biomass burning upwind in the Amazon basin is the major source
of the enhanced sulfate and nitrate imput.
Methods Regular rain and fogwater sampling along an altitude profile between 1800 and 3185 m has been carried out in the Podocarpus
National Park close to the Rio SanFrancisco (3°58'S, 79°5'W) in southern Ecuador. pH values, electrical conductivity and chemical
ion composition were measured at the TUM-WZW using standard methods.
Results and Discussion Results reported cover over one year from March 2002 until May 2003. Annual deposition rates of sulfate were calculated ranging
between 4 and 13 kg S/ha year, almost as high as in polluted central Europe. Nitrogen deposition via ammonia (1.5–4.4 kg N/ha
year) and nitrate (0.5–0.8 kg N/ha year) was found to be lower but still much higher than to be expected in such pristine
natural forest environment. By means of back trajectory analyses it can be shown that most of the enhanced sulfur and nitrogen
deposition is most likely due to forest fires far upwind of the Ecuadorian sampling site, showing a seasonal variation, with
sources predominantly found in the East/NorthEast during January–March (Colombia, Venezuela, Northern Brazil) and East/SouthEast
during July–September (Peru, Brazil).
Conclusion Our results show that biomass burning in the Amazon basin is the predominant source of sulfur and nitrogen compounds that
fertilize the mountaineous rain forest in south Ecuador.
Recommendation and Outlook The mountaineous rain forest in south Ecuador has developed on poor and acid soils, with low nutrient availability. The additional
fertilization resulting from anthropogenic biomass burning constitutes a significant disturbance of this ecosystem, its functioning
and biodiversity. Thus it is planned to employ isotope analyses for quantifying the pathways of nitrate and sulfate deposition
in these natural forests. 相似文献