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1.
通过有效解决建设用地子类划分,实现定量评价城市热环境的空间分异性,对改善城市生态环境、实现城市化的健康发展具有重要的意义和科学价值。论文以广州市为例,参考自然城市的概念,基于5类兴趣点(Point Of Interest,POI)开放数据,结合城市建设用地分类标准,构建5类自然区块;在Landsat 8遥感影像地表温度反演的基础上,计算分析自然区块下地表热场等级分布格局、热场平均值及热环境足迹范围,以对城市热环境空间分异性进行评价。研究表明:① 自然区块的构建,能准确地反映各类POI数据空间分布情况,能够实现对建设用地子类型的划分;② 5类自然区块内部地表热场等级均以高温像元为主,但等级分布具有显著差异。同时,自然区块的热场平均值由高到低的排序为:工业区块>商业服务业区块>交通与道路区块>居住区块>公共管理与服务区块;③ 自然区块形成的高温集聚区,存在热量扩散现象,实际影响范围大于其物理边界,5类自然区块的热环境足迹范围具有分异性。热环境足迹影响范围由大到小排序为:工业区块>商业服务业区块>居住区块>道路与交通区块>公共管理与服务区块。研究结果可为微观尺度上分析城市热环境、改善城市生态环境、实现城市化的健康发展提供科学依据。  相似文献   
2.
21世纪以来生态系统服务退化与人类需求提升间的矛盾愈发激烈,如何有效推进生态系统服务与人类福祉的协调平衡成为当前可持续发展的核心主题.论文通过梳理生态系统服务与人类福祉关系研究的阶段演进发现,现有研究主要从服务对福祉的影响与福祉对服务的反馈切人,逐步聚焦到供需关系与空间流动、权衡/协同的利益博弈、文化服务的价值化、生态...  相似文献   
3.
In this paper we present theBV photoelectric light curves of the W UMa-type eclipsing binary TY Pup. We have gained ephemerides by means of the times of minima. The obtained light curves have been solved using Wilson-Devinney's synthetic code. The results indicate that TY Pup is a contact system with mass ratio 0.185 and a large degree of overcontact of 52%. Combined with spectroscopic material, absolute parameters of TY Pup are derived. It may be concluded that TY Pup is an evolved contact binary.  相似文献   
4.
扎河坝坳陷位于阿尔泰造山带与准噶尔盆地之间,属于中亚造山带的一部分,自早古生代以来经历了准噶尔洋盆的打开和闭合等阶段,富含煤炭和金属矿产,也具有一定的油气勘探前景。研究区火山岩和含煤层系发育,地表风化剥蚀严重,对研究其地层发育特征和沉积环境起到了一定的制约。对扎河坝坳陷新富地1井岩芯样品开展沉积岩微量元素测试,分析结果表明,扎河坝坳陷上二叠统为温暖湿润的淡水沉积环境,表明扎河坝坳陷晚二叠世经历了火山活动和陆相淡水沉积2个阶段,印证了准噶尔洋由俯冲消减向陆内阶段转换的过程。该研究对恢复研究区构造演化及沉积古地理特征具有重要意义。  相似文献   
5.
正1研究目的(Objective)研究区位于塔里木盆地塔西南坳陷齐姆根凸起英吉沙背斜构造单元西南。该区勘探程度低,此前未进行高覆盖次数地震勘探、无钻井,石油地质条件尚不清楚。本次研究的目的是落实英吉沙—莎车地区齐姆根凸起侏罗系杨叶组烃源岩有效性;厘清英吉沙—莎车地区地层发育情况,确定苏盖特构造侏罗系与周边露头剖面对比关系;获取钻井地质资料,为该区地震地质层位标定提供依据,了解区内的地层及储盖组合发育情况,为进一步油气勘探评价提供基础资料。  相似文献   
6.
In this paper, we give theBV photoelectric light curves of the Algol-type eclipsing binary EU Hydrae. We have analysed its period by means of the times of minima determined from this observation and the times of minima which other observers published. The period was found to gradually decrease with a change rate dP/dE = -3 . d 29 × 10–10. The obtained light curves have been solved using Wilson-Devinney's synthetic light-curve program. The results demonstrate that EU Hydrae is a detached system, the secondary component fills the Roche-lobe, its mass ratio is 0.205. EU Hya may evolve to be a semidetached system in which the secondary component fills the Roche-lobe.  相似文献   
7.
On the basis of reprocessing 34 new two-dimensional spliced long sections(20,191 km) in the Tarim Basin, the deep structure features of the Tarim Basin were analyzed through interpreting 30,451 km of two-dimensional seismic data and compiling basic maps. Seismic interpretation and geological analysis conclude that the Nanhua-Sinian strata are a set of rift-depression depositional systems according to their tectonic and depositional features. The rift valley formed in the Nanhua Period, and the transformation became weaker during the late Sinian Period, which eventually turned into depression. From bottom to top, the deposited strata include mafic igneous, tillite, mudstone, and dolomite. Three major depocenters developed inside this basin during the rift stage and are distributed in the eastern Tarim Basin, the Awati area, and the southwestern Tarim Basin. Among them, the rift in the eastern Tarim Basin strikes in the near east-west direction on the plane and coincides with the aeromagnetic anomaly belt. This represents a strong magnetic zone formed by upwelling basic volcanic rock along high, steep normal faults of the Nanhua Period. Controlled by the tectonic background, two types of sedimentary systems were developed in the rift stage and depression stage, showing two types of sequence features in the Sinian depositional stage. The Nanhua System appears as a wedge-shaped formation, with its bottom in unconformable contact with the base. The rifting event has a strong influence on the current tectonic units in the Tarim Basin, and affects the distribution of source rock in the Yuertus Formation and reservoir beds in the Xiaoerbulake Formation in Lower Cambrian, as well as the gypseous cap rock in Middle Cambrian. The distribution features of the rifts have important and realistic significance for determining the direction of oil and gas exploration in the deep strata of the Tarim Basin. Comprehensive analysis suggests that the Tazhong region is the most favorable zone, and the Kalpin-Bachu region is the optimal potential zone for exploring sub-salt oil and gas in deep Cambrian strata.  相似文献   
8.
The changes in the orbital period of the short-period RS CVn-type binaryBH Vir are studied based on the analysis of the O-C curve formed by allphotoelectric times of light minimum. It was discovered that the orbitalperiod of BH Vir may show a periodic variation with a period of 9.12years. A weak evidence also indicating a small amplitude oscillation witha period of 52.7 years in the change of the orbital period. Two possiblemechanisms (light times effects due to two hypothetical additional bodiesand magnetic activity cycle) that could explained the period behavior arestudied. The periodic changes in the orbital period can be explained asdue either to magnetic activity cycles in the two components or to thelight-times effects of the additional bodies.  相似文献   
9.
The O–C curve of the contact binary CK Boo have been analyzed with Kalimeris et al. (1994) method. It is shown that the orbital period is changing in a quasi-sinusoidal form with a period of about ∼ 14 yr superposed on a secular period increase. The correlation of the variations of the light level at MinI, MaxI and II in the light curve implies that the luminosity of secondary component is variable. Comparing the change of the quasi-periodic component in the orbital period with that of the secondary's luminosity, we find that the luminosity of the secondary component and the orbital period may vary with the same cycle length ∼14 yr; the variation of the secondary's luminosity is in the same phase with that of the orbital period. This connection is different from those of the RS CVn-type close binaries (e.g. CG Cyg, V471 Tau, RT Lac). The mechanisms that may have produced this relation of the variations of the orbital period and the luminosity of the secondary are also discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
根据作者提出的确定食双星基本参量的一个新方法,由光变极小时刻求出了相接双星大熊座AW的基本参量。证实了Rensing等人为了矫正相接双星邻近效应引起的谱线轮廓畸变所提出的模型对该双星的适用性;同时也证实了Mochnaski提出的计算相接双星质量的理论模型对该双星的适用性。另外还确认了大熊座AW是一个已演化的零龄相接双星。  相似文献   
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