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551.
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E.K. Papadimitriou 《Waste management (New York, N.Y.)》2010,30(4):572-582
Commingled household waste (HW) that had a controlled composition was autoclaved at elevated pressures in the presence of saturated steam for one hour at the nominal temperature levels of 130 °C, 160 °C and 200 °C. The focus of this study was the impact of temperature/pressure on hydrolysis of organic matter during autoclaving and the extent of its hydrolysis. The pH decreased with autoclaving temperature with which it had a linear relationship, and ranged from 7.4 and 6 in floc, and 6.7 and 3.6 in steam condensate. Overall, organic matter solubilisation, as indicated by dissolved organic carbon, biological and chemical oxygen demands, and total dissolved solids, increased with temperature. Lignin did not appear to hydrolyse. Hemicellulose hydrolysed and degraded the most, followed by cellulose. The highest recoveries of hemicellulose and cellulose in solution were achieved at 160 °C, although the latter could be due to experimental error. The largest losses of hemicellulose and cellulose were recorded at 200 °C. The performance of the system in respect to hydrolysis was inferior compared to other hydrothermal systems, particularly those employing wet oxidation. 相似文献
553.
NOËLLE F. KÜMPEL E. J. MILNER‐GULLAND GUY COWLISHAW J. MARCUS ROWCLIFFE 《Conservation biology》2010,24(3):861-871
Abstract: Results of many studies show unsustainable levels of bushmeat hunting across West/Central Africa. Nevertheless, these results are usually derived from snapshot sustainability indices in which critical parameters are often taken from the literature. Simple, more informative tools for assessing sustainability are needed. We evaluated the impact of bushmeat hunting across a range of temporal, spatial, and taxonomic scales in a comparison of different measures of sustainability. Over 15 months in 2002–2004 in and around a village close to Equatorial Guinea's Monte Alén National Park, we collected data via a village offtake survey, hunter‐camp bushmeat‐consumption diaries, hunter interviews, and following hunters during hunts. We compared 2003 data with a previous offtake survey (1998–1999) and interview reports back to 1990. In the past 14 years, average distance from the village at which hunters operated remained constant, with hunters switching back and forth between long‐established camps, although trapping effort increased. In the past 5 years, overall offtake and number of active hunters did not change substantially, although catch per unit effort (CPUE) decreased slightly. Although the proportion of the two most commonly trapped species (Cephalophus monticola and Atherurus africanus) and gun‐hunted primates increased in the offtake, species presumably less robust to trapping decreased slightly. Apparent sustainability in economic terms may be masking gradual local extirpation of more vulnerable species before and during this study. Our results suggest that changes in prey profiles and CPUE may be the most accurate indicators of actual sustainability; these indices can be monitored with simple village‐based offtake surveys and hunter interviews to improve community management of bushmeat hunting. 相似文献
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M. S. Zaman E. W. Hupp F. E. Lancaster 《Journal of environmental science and health. Part. B》2013,48(5):621-638
Abstract Effects of ionizing radiation on brain myelination and some physical development parameters were studied in laboratory rats (Fisher F‐344 inbred strain). Rats were treated with three different doses of radiation (150 rad, 15 rad, and 6.8 rad) delivered on the 20th day of prenatal life. Exposure to 150 rad reduced body, brain, ovary, kidney, heart and spleen weights. Prenatal exposure to 150 rad of radiation reduced the cerebral cortex weight by 22 percent at 30 days of age, and 20 percent at 52 days of age which caused a reduction in cerebral cortex myelin content by 20 and 23 percent at the ages of 30 and 52 days respectively. This dose did not affect the myelin content of the cerebellum or the brain stem, or the myelin concentration (mg myelin/g brain tissue) of the cerebral cortex, cerebellum, and the brain stem. The cerebral cortex weight of the 15 rad treated rats was reduced at the age of 30 days. Exposure to 15 rad, and 6.8 rad did not affect either the myelin content or the myelin concentration of these brain areas. 相似文献
556.
The recent intensification of human disturbances in the Caribbean has increased the prevalence of partial mortality on coral colonies. Partial mortality can change colony size by directly shrinking colonies or by splitting colonies into fragments. A reduction in colony size can also adversely affect fecundity and fitness as internal resources shift away from reproduction toward colony maintenance. This study aimed to determine whether three Caribbean coral species, Siderastrea siderea, Montastraea faveolata, and Diploria strigosa, along the reef tract in Puerto Morelos, Mexico (20o52′N, 86o51′W), continued to dedicate resources to reproduction when colonies were fragmented to pre-maturation size. Contrary to expectations, eggs were found in colonies that were smaller than the maturation size and had been subjected to partial mortality. The continued dedication of resources toward reproduction, even in the smallest colonies, suggests that resource trade-offs away from reproduction are not as rigid as previously suggested in stressed corals. 相似文献
557.
Thomas R. Paradise 《Environmental Hazards》2013,12(3):167-180
Earthquakes are separated from other hazards in meaning, significance, and risk perception throughout the Islamic World due to their specific focus in their own chapter or surah “al-Zalzala” (99th) in the Qur'an. Unlike earthquakes that are discussed in terms or the Judgment Day or as divine punishment or retribution against the disbelieving or hypocritical—other natural hazards like floods, tornadoes, and landslides are rarely discussed. An extensive survey of earthquake survivors and longtime residents was undertaken to better understand the perceptions of seismic risk in Agadir, Morocco where two moderate earthquakes razed the city in 1960 leaving 15,000 dead and 25,000 injured. Most of the deaths were attributed to faulty construction (along with standards and enforcement), inaddition to poor evacuation plans. During the summer of 2002, more than 250 earthquake survivors and residents were surveyed and interviewed for their knowledge and perception of the disaster forty years before. Surveys were conducted in Arabic, French and English and included questions and Likertscaled responses including extensive interviews in the hopes of obtaining ideas of their potential quake recurrence, seismology, current construction standard policies, and local and regional planning strategies. In addition, reviews the Qur'an, Hadith and classical and contemporary tafasir texts were used to investigate the guiding passages used in Islamic discussions of “al-Zalzala”. It was found that younger persons (<25yo) were more likely to believed that brick, mortar and cement structures were always safer and stronger during and after a tremor, regardless as to whether they are iron-reinforced or sub-standard (and hazardous) stone or brick infilled. After the 1960 disaster, speedy recovery efforts often undermined concrete construction and reinforcement techniques since such ‘rebar’ was relatively unavailable. Even today, inferior and seismically unstable construction practices are widely used. It was found that television-watchers considered themselves less knowledgeable about earthquakes, when in fact many aspects of the1960 event and earthquakes in general, were more widely understood by this group, supporting the notion that the medium of televisionis the most widely used, efficient, and fastest mass communication and education tool. Less-educated respondents in general tended to attribute earthquakes to divine action and retribution. All questions, however, concerning the possibility of quake recurrence frequency or magnitude caused an overwhelming refusal to answer, or with the reply of ‘Allahu a'lam’ or “God is wisest”—implying or directly stating that any attempt at earthquake forecasting, quake-related construction, advanced architectural standards for seismic safety, and/or related education was ‘haram’ or prohibited by Islam. Further discussions with participants in Agadir indicated that any guess, awareness or prediction was in fact, fortune-telling and therefore an act forbidden by the Qur'an and Hadith. Finally, the less educated were more likely to say that Allah protected those who were devout and considered scientific assessment as futile, forecasting as forbidden, or new construction technologies as a waste since only the ‘kafir’ (non-Muslim) or ‘munafiq’ (hypocrite) were at risk to death or injury from an earthquake. These conclusions are important toward gaining an insight of perception and risky behavior in a questionably constructed city with now more than 600,000 people 40 years later, and in a region laced by active faulting. 相似文献
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