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941.
XUE Desheng HUANG Gengzhi GUAN Jingwen LIN Jiarong 《中国地理科学(英文版)》2014,24(5):607-619
By focusing on Guangzhou, this paper examines how different concepts of city in terms of urban-rural relationships are shaped in transforming China since 1949, and explores how they influence the way in which urban planning are practiced. In the pre-reform era, the city was defined as a productive space under the system of urban-rural segregation established for securing rapid industrialization. Urban planning was thus only concerned with the development of urban areas. In the 1980s and 1990s after the reform, institutional change and economic transformation mobilized the urban-rural linkages. The development of suburban areas was then con- sidered by urban planning, but this consideration was a passive response to urban problems such as population explosion and water re- sources protection. Since the new millennium, the agenda for sustainable development and problems of uneven urban-rural development have called for the development of urban-rural integration. In this context, the city is conceptualized as a complex of mountain, city, river, farmland and sea, reconstructing the ideology of urban-rural division in defining urban development. Urban planning has therefore sought in an active way to develop a sustainable city embracing rural and natural elements, and to balance economic growth and envi- ronmental protection. It is argued that developing the concept of city as a complex of urban and rural elements contributes to the urban planning for sustainable urban development, while this conceptualization relies on the recognition of the integrated urban-rural relationship. 相似文献
942.
<正>Erratum to:Chinese Journal of Oceanology and Limnology Vol.31 No.6,P.1356-1367,2013http://dx.doi.org/10.1007/s00343-014-3019-4The supporting grant information on the footnote of the original version of this article needs to be altered and updated.The new information is given below. 相似文献
943.
??????????????????????????????????????б????÷??????GNSS??????????飬?????????????????????????????????????????????????仯????????????????????????????????????3 mm??1 mm?????????????????????????????????2 mm??0.2 mm??????????仯?????????о???????????????????2?仯????????????????????????????仯????????峱??????????????????????????????????????????????????????????????????????????????????????????????????????????? 相似文献
944.
The molecular basis of color polymorphism in the shells of the pearl oyster Pinctada fucata is largely unknown. We developed a red-shelled family line and used suppression subtractive hybridization (SSH) to screen for differentially expressed genes in red- and non-red-shelled pearl oysters. We constructed forward and reverse cDNA subtractive libraries consisting of 2 506 and 797 clones, respectively. Among 343 randomly selected clones in the forward library, 304 sequences were identified in GenBank using BLASTx and BLASTn. Of the 304 sequences, 13 showed no similarity to known sequences and 291 were matched with known genes of the pearl oyster, including shematrin-1, shematrin-2, shematrin-6, shematrin-7, nacrein, nacrein-like protein, aspein for shell matrix protein, glycine-rich protein, mantle gene 5, 28S, EST00031, EST00036, 16S, and COΙ. In the reverse library, 7 clones were sequenced and analyzed by BLAST. Two sequences shared similarity with EST00036 from the P. fucata subtraction cDNA library, four with the P. fucata mitochondrial gene for 16S rRNA and 1 with P. fucata shematrin-2. We evaluated the expression of 12 genes from the forward library using RT PCR. Two sequences matched with 16S and COΙ so were considered to be false positives. The remaining 10 sequences were differentially expression in the red-shelled pearl oysters. Our results suggest that differential expression of these genes may be related to color variation in the red-shelled family line of the pearl oyster. 相似文献
945.
Seismic damage simulation in urban areas based on a high-fidelity structural model and a physics engine 总被引:1,自引:1,他引:0
Effective seismic damage simulation is an important task in improving earthquake resistance and safety of dense urban areas. There exist two significant technical challenges for realizing such a simulation: accurate prediction and realistic display. A high-fidelity structural model is proposed herein to accurately predict the seismic damage that was inflicted on a large number of buildings in an urban area via time-history analysis, with which the local damage to different building stories is also explicitly obtained. The accuracy and efficiency of the proposed model are validated by a refined finite element analysis of a typical building. A physics engine-based algorithm is also proposed that realistically displays building collapse, thus overcoming the limitations of the high-fidelity structural model. Furthermore, a visualization system integrating the proposed model and collapse simulation is developed so as to completely display the seismic damage in detail. Finally, the simulated seismic damage of a real medium-sized Chinese city is evaluated to demonstrate the advantages of the proposed techniques, which can provide critically important reference information for urban disaster prevention and mitigation. 相似文献
946.
NIE Fei DONG Guochen MO Xuanxue WANG Xi FAN Wenyu DONG Meiling ZHU Huaping 《《地质学报》英文版》2014,88(3):754-765
The Kejie pluton is located in the north of the Changning-Menglian suture zone. The rock types are mainly biotite-granite. Zircon LA-ICP-MS U-Pb dating indicates that the Kejie pluton emplaced at about 80–77 Ma, Late Cretaceous. The Kejie pluton samples are characterized by high SiO2(71.68%–72.47%), K2O(4.73%–5.54%), total alkali(K2O + Na2O = 8.21%–8.53%), K2O/Na2O ratios(1.36–1.94) and low P2O5(0.13%–0.17%), with A/CNK of 1.025–1.055; enriched in U, Th, and K, depleted in Ba, Nb, Sr, Ti, P and Eu. They are highly fractionated, slightly peraluminous I-type granite. The two samples of the Kejie pluton give a large variation of εHf(t) values(-5.04 to 1.96) and Hf isotope crustal model ages of 1.16–1.5 Ga. Zircon Hf isotopes and zircon saturation temperatures of whole-rock(801°C–823°C) show that the mantle-derived materials maybe have played a vital role in the generation of the Kejie pluton. The Kejie pluton was most likely generated in a setting associated with the eastward subduction of the neo-Tethys ocean, where intrusion of mantle wedge basaltic magmas in the crust caused the anatexis of the latter, forming hybrid melts, which subsequently experienced high-degree fractional crystallization. 相似文献
947.
安徽柯村A型花岗岩岩墙群地质地球化学特征及构造环境 总被引:4,自引:0,他引:4
柯村岩墙群岩石具文象结构,地球化学上具富硅、富碱、富Ga、Zr、Nb、F,低铝、贫水和Ba、Sr特征。在多种判别图上,均投影在A型花岗岩区。根据岩石地球化学特征和产出构造环境分析,柯村岩墙群属非造山区裂图1柯村碱性花岗岩岩墙群地质略图Fig.1Thealkalinegranitedykecluster,Kecun.谷A型花岗岩。 相似文献
948.
湖相致密油资源地球化学评价技术和应用 总被引:1,自引:0,他引:1
湖相致密油或页岩油资源量和可采性评价关键问题:一是在什么地方;二是有多少;三是有多少可采出。本文讨论了解决这3个问题的关键性地质技术和理论。湖相致密油勘探层空间分布识别的关键是高有机丰度源岩层段和含油夹层精细识别。利用源岩测井地球化学评价技术可识别出湖相地层中不同w(TOC)区间的源岩层段,利用氢指数(IH)与w(TOC)的相关性,可实现湖相源岩层非均质性精细表征。湖相致密油勘探层油的赋存形式分为两类:一是致密油勘探层中砂岩、粉砂岩和碳酸盐岩夹层中的油,呈游离态;二是富有机质源岩中的油,包括了吸附态和游离态。吸附油在目前的技术条件下难以开采,现阶段真正有工业价值的是游离油。根据实际地球化学数据可标定出源岩中游离油量和吸附油量模型,从而可计算出游离油量、吸附油量和总原地油量。致密油流动性控制了其可采性,而源岩成熟度和生烃转化率是控制烃类流动性的关键。利用湖相高丰度源岩(w(TOC)>2%)IH演化可较高精度地标定源岩的成熟度和转化率。以泌阳盆地为例展示了如何从源岩生烃模型和实际岩石热解数据预测页岩油的流动性。 相似文献
949.
This article presents an improved p arallel R aster P rocessing L ibrary – pRPL version 2.0. Since the release of version 1.0, a series of modifications has been made in pRPL to improve its usability, flexibility, and performance. While retaining some of the key features of pRPL, the new version has gained several new features: (1) a new DataManager class has been added for integrated data management, and to facilitate data decomposition, assignment mapping, data distribution, Transition execution, and load‐balancing; (2) a GDAL‐based raster data I/O mechanism has been added to support various geospatial raster data formats, and provide centralized and pseudo parallel I/O modes; and (3) a static load‐balancing mode and a dynamic load‐balancing mode using the task‐farming technique are provided. A parallel zonal statistics tool and a parallel Cellular Automata model were developed to demonstrate the usability and performance of pRPL 2.0. The experiments using the California datasets showed that the performance altered when different pRPL options (i.e. load‐balancing mode, I/O mode and writer mode) were used for different algorithms, datasets, and varying numbers of processes. 相似文献
950.
羌塘盆地地处青藏高原腹地,油气资源丰富,是我国目前唯一未大规模勘探的含油气盆地。研究其地质结构,将为青藏高原科学考察与油气地质条件评价奠立重要基础。本文针对羌塘盆地“古生代南、北基底有别,中生代周缘板块构造边界限制,新生代陆内构造变形强烈”这一典型的缝合带上的多旋回复合、叠合盆地,利用盆地内部的钻井与高精度反射地震剖面对其分层地质结构进行研究。结果表明,羌塘盆地发育上三叠统肖茶卡组,中‑下侏罗统雀莫错组,中侏罗统布曲组与中侏罗统夏里组泥岩、膏岩、膏泥岩等4套区域性滑脱层;此外,还发育下侏罗统曲色组泥质岩,上侏罗统索瓦组的泥灰岩、泥岩,始新统唢呐湖组的膏盐、泥岩,二叠系煤层等4套局部性滑脱层;基底内部发育韧性剪切层。它们在垂向上将羌塘盆地分划为软弱层与能干层相间的多套组合。受区域性滑脱层控制,羌塘盆地发育分层变形系统;滑脱层上、下构造几何学样式差异较大,运动学指向也不一致;整体表现为大型多重滑脱构造变形系统。分层滑脱变形系统约束了油气保存单元的分布。分层滑脱变形将为进一步认识羌塘盆地,评价羌塘盆地的油气保存单元提供新的学术思路。
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