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1.
芥川龙之介的《水虎》与果戈理的《狂人日记》、鲁迅的《狂人日记》均采用了现实主义与象征主义相结合的创作方法,一针见血地揭露了社会制度的黑暗与腐朽。但他们在创作方法上使用的象征主义和对社会现实揭露的广度与深度不完全相同,主人公的思想高度更是各不相同。作品创作的背景、历史条件,作者的思想高度、性格特点和创作风格是造成这些差别的根源。  相似文献   
2.
Dispersal is a life history trait that plays a key role in population dynamics. We used camera traps to estimate the distance male and female tigers (Panthera tigris) dispersed from Ranthambhore Tiger Reserve (RTR) in semi-arid habitats of western India from 2003 to 2010. We deployed camera traps whenever tiger tracks were found in places adjacent to protected areas where tigers had not been recently reported. We identified tigers by matching strip patterns by using their photographs with the database of camera-trapped tigers of RTR at the Wildlife Institute of India, Dehradun. We determined the aerial distance (straight line) between the last location of photo-capture in the natal area (in RTR) and the location of the most recent photo-capture. One female and three male tigers that dispersed from RTR were identified from photographs. The longest distance dispersed by a tiger was 148.4 km, and the average dispersed distance was 124.2 ± 23.7 km (n = 3) for male tigers and 78.4 km for the female tiger. The minimum age of the male tigers when they dispersed was 24 months. These data are important for making conservation and management decisions for restoration of potential connectivity between landscapes.  相似文献   
3.
Remote sensing digital image analysis has been applied to monitor land clearing and degradation processes on a plateau covered by tiger bush near Niamey in South West Niger, where signs of severe landscape degradation due to fuelwood supply have been observed in the last decades. A MODIS NDVI dataset (2000–2015) and five LANDSAT images (1986–2012) were used to identify spatial and temporal dynamics and to emphasize areas of greater degradation. The study indicates that the land clearing found by previous investigations in the second part of the 20th century is still ongoing, with a decreasing trend of MODIS NDVI values recorded in the period 2000–2015. This trend appeared to be linked to an increase in bare soil areas that was demonstrated by analysis of LANDSAT SAVI images. The investigation also indicated that rates of degradation are stronger in more deteriorated areas like those located nearer Niamey; degradation patterns also tend to increase from the inner areas to the edges of the plateau. These results attest to the urgency to develop effective environmental preservation policies and find alternative solutions for domestic energy supply.  相似文献   
4.
Phase fractionation can strongly deplete oil of its volatile compounds in a regular and characteristic fashion. This process has affected oils to a remarkably uniform extent throughout the 30 × 15 km South Marsh Island 208–239 and Vermilion 30–31 area (including the Tiger Shoal, Starfak, Mound Point, Lighthouse Point, Amber, Trinity Shoal, and Aquamarine fields) just offshore Louisiana. Fractionation of the original “parent” oil likely occurred in the deep, relatively flat-lying Rob L sand that underlies the area, and produced gas-washed oils (mean API 33°) and gas condensates (mean API 50°) in a volume ratio of 1:3.5. Both fractionated oil and vapor migrated from the fractionation site to shallower reservoirs. However, the estimated ultimate production ratio of gas-washed oil to gas condensate in this group of fields is 1:0.32, about 11 times higher than would be expected on mass balance considerations alone. Thus, there is an apparent deficiency of producible gas condensate relative to the amount of producible oil for the entire study area and for every field in that area. In the case of the Tiger Shoal field, the ratio of industry-estimated ultimately producible oil to gas condensate is 1:1.1. Based on the production data, we conclude that either there is an additional 6.4 × 106 m3 (43 MMbbl) of undiscovered and/or unproduced condensate in the area or that condensate has escaped preferentially in vapor form to the seafloor. The well-studied and nearly depleted Tiger Shoal field provides a good example of how chemical data can be analyzed in a way that contributes insight into the phase fractionation process and the remaining exploration potential of an area.  相似文献   
5.
玉龙雪山位于青藏高原东南缘,它以其独特的地貌特征而引人关注。其顶部为一古残留面,在30×20km2范围内海拔>5000m的山峰达18座,高出其周围地区平均海拔近1000m。在分析该区地质地貌特征基础上,我们根据岩石圈弹性挠曲地壳均衡理论,以较保守的残留面海拔4250m为当时金沙江下切玉龙雪山的基准面,结果表明:由于虎跳峡中大规模物质剥蚀而引起玉龙雪山地壳均衡反弹,导致山体隆升了468m,这完全是侵蚀作用对于玉龙雪山隆升的贡献。而玉龙雪山与周围地区的剩余地势高差,主要由正断层等构造作用造成。因此,玉龙雪山的隆升是侵蚀与构造作用共同控制的结果。该区最大量地壳均衡反弹的触发机制是5.02.5M a期间玉龙雪山东西两侧正断层的发生。另一方面,作为玉龙雪山的南东延伸部分——点苍山(4122m)在5.02.5M a同样也发生了构造伸展,但是没有遭受大规模的河流侵蚀作用,因此其海拔相对要低很多。这进一步说明地壳均衡反弹导致了玉龙雪山隆升,并加大了玉龙雪山与点苍山在原有基础上的地势高差。  相似文献   
6.
Multi-temporal very high resolution satellite images and field work have been used for quantifying the tree cutting rate over a 5 years period in a very arid tiger bush area of North Eastern Somalia with intensive charcoal production activities. By applying both a classical area frame sampling approach with visual interpretation of the samples and a semi-automatic tree detection algorithm, it was possible to create baseline tree density layers for the 2 years of observation and to quantify the tree cutting rates for the period from 2001 to 2006. An average annual tree loss of −2.8%, coupled with the total absence of regrowth during the 5 years study period, confirm the tremendous ecological impacts of charcoal driven tree cutting on tiger bush vegetation. Analysis of the results evidences spatial and temporal patterns in the cutting locations and poses the basis for a better understanding of the ecological and human dimensions of deforestation in the fragile rangeland environment of Northern Somalia.  相似文献   
7.
A sulfide chimney ore sampled from the flank of the active Tiger vent area in the Yonaguni Knoll IV hydrothermal field, south Okinawa trough, consists of anhydrite, pyrite, sphalerite, galena, chalcopyrite and bismuthinite. Electron microprobe analysis indicates that the chalcopyrite contains up to 2.4 wt% Sn, whereas bismuthinite contains up to 1.7 wt% Pt, 0.8 wt% Cu and 0.5 wt% Fe. The Sn‐rich chalcopyrite and Pt–Cu–Fe‐bearing bismuthinite are the first reported occurrence of such minerals in an active submarine hydrothermal system. The results confirm that Sn enters the chalcopyrite as a solid solution towards stannite by the coupled substitution of Sn4+Fe2+ for Fe3+Fe3+, whereas Pt, Cu and Fe enter the bismuthinite structure as a solid solution during rapid nucleation. The fluid inclusions homogenization temperatures in anhydrite (220–310°C) and measured end‐member temperature of the vent fluids on‐site (325°C) indicate that Sn‐bearing chalcopyrite and Pt–Cu–Fe‐bearing bismuthinite express the original composition of the minerals that precipitated as metastable phases at a temperature above 300°C. The result observed in this study implies that sulfides in ancient volcanogenic massive sulfide deposits have similar trace element distribution during nucleation but it is remobilised during diagenesis, metamorphism or supergene enrichment processes.  相似文献   
8.
以陕西"周老虎"做比较,指出广州"麦船台"同为假点.上世纪70年代麦英豪定性的"秦汉造船工场遗址",30多年来始终得不到造船工程界和船史学界的认同,地理和地质学界认为这里并不存在造船和下水的条件,建筑工程和建筑考古学界则以大量出土文物证实其为南越王宫苑遗址.被国务院确定为国家重点文物保护单位的"秦造船工场遗址"既无保护,又无展出,也没有专著出版,在全国的学术界出现一片质疑和遣责声.这是麦英豪以排他性的专家"鉴研会"排斥多学科的全国性学术研讨会.文中呼吁麦英豪应正视现实,修正失误,广州的文物部门领导也应当检讨不作为的过失.  相似文献   
9.
芥川龙之介的《水虎》与果戈理的《狂人日记》、鲁迅的《狂人日记》均采用了现实主义与象征主义相结合的创作方法,一针见血地揭露了社会制度的黑暗与腐朽。但他们在创作方法上使用的象征主义和对社会现实揭露的广度与深度不完全相同,主人公的思想高度更是各不相同。作品创作的背景、历史条件,作者的思想高度、性格特点和创作风格是造成这些差别的根源。  相似文献   
10.
India's Sundarbans region lies within the state of West Bengal and is part of the world's largest mangrove ecosystem. Low-intensity shrimp aquaculture is present, but the potential exists for more intensive development. We argue for avoiding environmental damage and social conflict by adopting appropriate policies now. In this study, we combine ecological simulations and a choice experiment to evaluate several policy scenarios. Such comparative evaluations combining different disciplinary tools are rare. While our ecological modelling supports severe restrictions on shrimp farming activities, local stakeholders prefer a more diverse strategy. Both models indicate that large-scale commercial shrimp aquaculture is least desirable.  相似文献   
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