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1.
本文采用H2O2/NaOH对玉米秸秆(RCS)进行改性来制备可吸附石油的生物质吸附剂(HNCS)。通过模拟实验,比较了不同改性时间的HNCS吸油量,发现改性14h的吸油量最大,达14.08g·g-1,而改性前RCS仅为4.33g·g-1,改性使得吸油量提高了325%,且吸油速率更快。通过扫描电子显微镜(SEM)、比表面积/孔隙度分析仪和傅里叶红外光谱仪(FT-IR),对改性前后样品结构进行表征,同时采用洗涤剂法和硫酸法对纤维素、半纤维素、木质素含量进行测定,结果发现:改性后的HNCS表面更加粗糙,且出现大量的吸附孔隙,比表面积为7.14m·2g-1,表面亲水性官能团减少,纤维素含量增加而木质素含量减少。这说明吸油量和吸油速率受到吸附剂表面官能团、比表面积和孔隙/间隙的影响。  相似文献   

2.
A spill of fuel oil at West Falmouth, Massachusetts, in 1969, contaminated contiguous salt marshes with up to 6000 micrograms of oil per gram (ppm) of wet mud and affected local populations of Uca pugnax. Directly related to high-sediment oil content were reduced crab density, reduced ratio of females to males, reduced juvenile settlement, heavy overwinter mortality, incorporation of oil into body tissues, behavioral disorders such as locomotor impairment, and abnormal burrow construction. Concentrations of weathered fuel oil greater than 1000 ppm were directly toxic to adults, while those of 100 to 200 ppm were toxic to juveniles. Cumulative effects occurred at lower concentrations. Recovery of the marsh from this relatively small oil spill is still incomplete after 7 years.  相似文献   

3.
In this article estimates are made of the permanent and reversible components of changes in heating oil use in major countries of the Organization for Economic Cooperation and Development. The components of the increase in oil use through the mid-1970's, and of the subsequent decline, are revealed. For seven countries, residential oil use decreased by 40 percent between 1972 and 1983, for a savings of about 1.2 million barrels per day (59 million metric tons of oil equivalent per year). One-third of this resulted from reductions in the number of homes heated with oil, the rest from reductions in oil use per oil-heated home. During that time, however, the size of these homes and the penetration of central heating increased significantly, so these figures underestimate the actual conservation achieved. Of the total oil savings, at least 46 percent are of a permanent nature, while the rest could be reversed with a continued slide in oil prices, although it seems likely that most of the savings will be maintained and may even increase.  相似文献   

4.
杭州木荷次生林生物量的研究   总被引:6,自引:4,他引:6  
杭州西湖山区北高峰南坡的木荷次生林的生物量、生长量及凋落量的调查结果表明:①林分总生物量为134.113t/hm~2,其中活植物体126.649t/hm~2;②总生物量各个层次分配比例为:乔木层80.16%,更新层5.67%,灌木层3.84%,草本层4.76%,枯落物层5.57%;③在乔木层中,干、枝和叶的生物量分别分53.591,16.996和4.835t/hm~2,占地上部分的70.95%,22.50%和6.40%,根生物量18.474t/hm~2,占该层生物量的29.76%;④全林年生长量18.474t/hm~2,乔木层12.598t/hm~2,占68.19%,更新层1.948t/hm~2,占10.54%;⑤年平均凋落量5.848t/hm~2,叶凋落量占79.49%。2~4月和8~9月分别是凋落的两个高峰季节。  相似文献   

5.
国内海上油运的迅速发展将导致船舶溢油事故风险逐年增大,科学的船舶溢油事故风险评估作为船舶溢油事故防控工作的重要方面也越来越受到重视。通过对我国以往船舶溢油事故的综合分析,借助国内外溢油事故数据和科学的评估方法,对舟山港的溢油事故发生概率和溢油量进行了预测和评估。得出的结论和建议将为船舶溢油事故应急能力建设提供参考和初步依据。  相似文献   

6.
构建了海洋与溢油模型相耦合的长江河口的溢油轨迹预报系统,海洋模型能较好模拟该海域的表层流场;溢油模型采用拉格朗日和随机游走的油粒子追踪法,可快速预测油粒子的漂移扩散轨迹和扫海面积。研究表明,大潮时溢油的油粒子的分布范围和扫海面积均比小潮时刻大,在南支溢出的油粒子会漂移到南、北港和南、北槽,对生态环境危害最大,会影响陈行和青草沙两大水库取水口,并对中华鲟和九段沙湿地保护区产生潜在的生态危害;在北支溢出的油粒子主要分布在北支水道和两岸,如果溢油点位于上段会倒灌进南支水道,将会产生较大的生态危害;在南港溢出的油粒子会漂移到南北槽,不会对两大水库和中华鲟保护区产生危害,但会对九段沙保护区造成潜在的危害;在北港溢出的油粒子则会漂移到崇明岛外海,且扩散范围很大,只对中华鲟保护区造成危害。  相似文献   

7.
In 1986 more than 8 million liters of crude oil spilled into a complex region of mangroves, seagrasses, and coral reefs just east of the Caribbean entrance to the Panama Canal. This was the largest recorded spill into coastal habitats in the tropical Americas. Many population of plants and animals in both oiled and unoiled sites had been studied previously, thereby providing an unprecedented measure of ecological variation before the spill. Documenation of the spread of oil and its biological begun immediately. Intertidal mangroves, algae, and associated invertebrates were covered by oil and died soon after. More surprisingly, there was also extensive mortality of shallow subtidal reef corals and infauna of seagrass beds. After 1.5 years only some organisms in areas exposed to the open sea have recovered.  相似文献   

8.
溢油鉴别是确定海上溢油事故污染源的重要的科技手段。采用普通荧光光谱法对16种油品的谱图信息进行提取鉴别。实验结果显示,对于不同种类的油品,由于其荧光光谱谱图信息相差较大,使用普通荧光光谱法很容易就可以区分开;而对于同一类型油品,由于其组分特征相似,荧光光谱的特征峰数目及其峰谷位置相近,鉴别起来存在一定困难。因此,在实际操作中可以考虑将普通荧光光谱法作为溢油鉴别程序中的初选步骤。  相似文献   

9.
A large quantity of lumber was spilled in the ocean off central California during the winter of 1978, and it spread through most of the range of the threatened California sea otter population within 4 weeks. The movement rates of lumber were similar to those of oil slicks observed elsewhere. These observations indicate that a major oil spill could expose significant numbers of California sea otters to oil contamination.  相似文献   

10.
The probable range of seepage into the marine environment is 0.2 x 10(6) to 6.0 x 10(6) metric tons per year. Within this range the best estimate for the present marine seepage worldwide is on the order of 0.6 x 10(6) metric tons per year. This estimate is based on the presumption that only a few other areas around the world are as seepage-prone as southern California. Measurements of seeps and seepage rates are too few to allow an accurate estimation by observation and measurement techniques alone. Seepage potential can, however, be related to geologic criteria, and these provide sound bases for marine seepage assessment. On the basis of this estimate, areas of high seepage potential contribute about 45 percent of the worldwide seepage, areas of moderate seepage about 55 percent, and areas of low seepage less than 1 percent. The situation varies somewhat from ocean to ocean. In the Pacific Ocean, areas of high seep potential are by far the major contributors. In the Atlantic, Indian, Arctic, and Southern oceans, areas of moderate seep potential are most significant because areas of high seep potential are relatively rare in these realnis. The circum-Pacific area is the area of greatest seepage; it contributes about 40 percent of the world's total.  相似文献   

11.
利用MODIS和Radarsat-2遥感数据对大连新港2010年7月16日的海上溢油信息进行提取分析,经过预处理的MODIS遥感数据,采用波段运算提取出溢油信息。较高分辨率的Radarsat-2数据经过几何校正、滤波等预处理,根据溢油的特点采用纹理分析法提取出边界明显的溢油信息,并与MODIS的溢油结果进行比较分析,排除MODIS图像上的非溢油信息,实现两种数据的优势互补。利用ArcGIS 9.3软件分别对2010年7月18日的MODIS数据和2010年7月19日的Radarsat-2数据提取出的溢油区域进行面积计算,其结果分别为174km2和198 km2与中国海监船的报道相符合,说明了此方法的可行性。  相似文献   

12.
It is difficult to estimate the area affected by an oil spill at sea, the degree of coverage by oil pollutants within the affected area, and the quantity of pollutants involved. Estimates of volumes and flow rates are based on estimated changes in areal extent of the spill. Uncertainties in measurement of area degrade the accuracy of estimating other parameters. To resolve this problem, available stock components have now been assembled into a system that yields repeatable, economical measurement of the areal extent of oil spills at acceptable levels of accuracy. The system comprises overflights with a thermal infrared imaging system, densitometric color enhancement of the infrared images, and automatic digital planimetry of the areas of specified image densities.  相似文献   

13.
河北省分季粮食产量预测研究   总被引:1,自引:0,他引:1  
在综合分析河北省粮食产量影响因素的基础上,运用回归分析、时间序列分析和专家经验分析等预测和决策方法,建立了河北省粮食总产和夏粮的多因素预测模型,该模型的拟合优度高于其他模型。应用模型预测了2013年河北省粮食总产和分季粮食产量,结果表明,若不发生大面积的自然灾害,2013年河北省粮食总产将达到3311.7万t,比2012年增加65.1万t,增长2.0%。其中,夏粮产量约为1366.8万t,比2012年增加13.7万t,增长1.0%;秋粮产量约为1944.9万t,比2012年增加51.4万t,增长2.7%。  相似文献   

14.
对2012年中国蔬菜进出口情况进行了分析,结果表明,2012年中国进口蔬菜约21.14万t,合计2.84亿美元,进口量、值同比分别增长32.56%和35.87%;加工蔬菜和干蔬菜进口明显增长,其中加工蔬菜进口16.19万t,同比增33.36%,干蔬菜进口2.32万t,同比增100.86%;美国、东南亚国家和地区是主要的蔬菜进口来源地,非洲来源蔬菜大幅增长;亚洲其他国家和地区是中国蔬菜主要出口地;受多种因素影响,全年蔬菜出口约934.28万t,合计98.21亿美元,出口量、值同比分别减少3.97%和15.52%,其中干蔬菜出口量、值大幅减少,同比分别减少25.86%和36.79%;月度进出口量波动增长,不同大类间有所差异。整体看,2012年中国蔬菜在国际市场上继续保持比较优势,进出口继续呈贸易顺差态势,预计这种趋势短期内不会发生变化,中国蔬菜进出口贸易将继续保持良好发展态势。  相似文献   

15.
近年来,海洋溢油事故频发,海洋溢油不可避免地对天然渔业资源造成巨大损害,如何正确、合理、快速地评估海洋溢油事故对天然渔业资源损害成为国内外关注的焦点。然而此类案件在司法实践中存在司法与鉴定、评估之间缺乏有机衔接的问题,为此,本文在总结已有文献和标准的基础上,结合课题组相关工作和典型司法实践,提出了一套易操作的海洋溢油对天然渔业资源损害司法鉴定程序与评估方法,以促进海洋溢油事故天然渔业资源损害鉴定评估工作的规范化。  相似文献   

16.
通过环境动力数据采集技术、溢油预测检验技术及应急决策三维技术实现一整套溢油应急决策系统.该系统通过ZigBee网络技术,将多功能航标船上的环境数据采集单元的实时数据传输至VTS服务器.服务器运行有环境动力预报模型、溢油模型、环境动力数据验证模型和虚拟现实仿真模型.该系统将实时环境动力数据引入验证模型,将会极大提高海事管理人员的决策准确性及应急能力.  相似文献   

17.
Methane was the most abundant hydrocarbon released during the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. Beyond relevancy to this anthropogenic event, this methane release simulates a rapid and relatively short-term natural release from hydrates into deep water. Based on methane and oxygen distributions measured at 207 stations throughout the affected region, we find that within ~120 days from the onset of release ~3.0 × 10(10) to 3.9 × 10(10) moles of oxygen were respired, primarily by methanotrophs, and left behind a residual microbial community containing methanotrophic bacteria. We suggest that a vigorous deepwater bacterial bloom respired nearly all the released methane within this time, and that by analogy, large-scale releases of methane from hydrate in the deep ocean are likely to be met by a similarly rapid methanotrophic response.  相似文献   

18.
Shanks AL 《Science (New York, N.Y.)》1987,235(4793):1198-1200
Internal waves generated by tidal currents concentrated and transported an oil spill (liquid asphalt) onshore. Plankton net samples were collected in front of and behind a set of internal waves as well as in the convergence and divergence zones over the waves. Tar "balls" were most abundant (greater than 30-fold) in the samples from the convergence zone. Comparison of the abundance of tar balls in front of and behind the set of waves suggests that the internal waves "caught" about 68% of the asphalt encountered and concentrated and swept shoreward tar balls from almost 8 kilometers of ocean.  相似文献   

19.
程黔 《农业展望》2013,9(2):4-7
2012年,在供需格局偏紧及最低收购价上调等因素支撑下,国内小麦市场迎来历史性辉煌。现货市场价格屡创历史新高,全国主要粮油批发市场三等白小麦交易均价为2355元/t,月比涨56元/t,较2011年同期上涨280元/t,年涨13.49%;各主产区累计收购新产小麦5619.1万t,比2011年同期增加281.7万t;虽然小麦播种面积略有下降,但单产大幅提高使得全国小麦产量达12058万t,较2011年增产318万t。预计2012/13年度全国小麦供给量约12260万t,需求量约12050万t,年度结余210万t,相比2011/12年度小麦供需有所改善;2013年国内小麦市场行情整体上涨格局不变,但在供需与政策影响下,价格波动空间或将加大,不排除出现阶段性行情。  相似文献   

20.
Atmospheric carbon dioxide and carbon reservoir changes   总被引:1,自引:0,他引:1  
The net release of CO(2) from the biosphere to the atmosphere between 1850 and 1950 is estimated to amount to 1.2 x 10(9) tons of carbon per year. During this interval, changes in land use reduced the total terrestrial biomass by 7 percent. There has been a smaller reduction in biomass over the last few decades. In the middle 19th century the air had a CO(2) content of approximately 268 parts per millon, and the total increase in atmospheric CO(2) content since 1850 has been 18 percent. Major sinks for fossil fuel CO(2) are the thermocline regions of large oceanic gyres. About 34 percent of the excess CO(2) generated so far is stored in surface and thermocline gyre waters, and 13 percent has been advected into the deep sea. This leaves an airborne fraction of 53 percent.  相似文献   

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