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1.
格尔木河格尔木站年径流特征及丰平枯水年划分   总被引:2,自引:0,他引:2  
温川  殷战阳 《科技信息》2011,(13):447-447,450
格尔木河是柴达木盆地水资源利用率较高的河流之一,因此研究流域控制站格尔木水文站年流特征及丰平枯水年划分,对水资源可持续利用具有十分重要意义。  相似文献   

2.
世界上海拔最高、线路最长的铁路——青藏铁路   总被引:1,自引:1,他引:0  
《科技导报(北京)》2005,23(1):28-28
青藏铁路是我国西部大开发的标志性工程,由青海省西宁市至西藏自治区拉萨市,全长1956km;其中一期工程西宁至格尔木南山口站846km,1979年建成铺通,1984年投入运营。正在修建的格尔木至拉萨段属二期工程,自格尔木起,沿青藏公路南行,经纳赤台、五道梁、沱沱河、雁石坪,翻越唐古拉山,再经西藏自治区安多、那曲、当雄、羊八井,  相似文献   

3.
本文利用格尔木1971—2010年40年的气象资料,统计分析了影响人体舒适度的气象要素变化规律。笔者在参考国内外对人体舒适度预报方法研究的基础上,结合格尔木特殊的气候特点,建立了格尔木城市人体舒适度预报方法,并通过检验在日常业务中投入运行,结果表明,该方法较为科学,符合实际,能满足公众对人体舒适度的气象服务需要。  相似文献   

4.
马刚 《科技信息》2011,(17):I0344-I0345
城市特色代表着城市的个性及其文化品格,是一座城市明显区别于其他城市的个性特征。特色鲜明的城市能够产生独特的城市景观,使城市具有持久的生命力和永恒的魅力。本文从探讨国内外城市特色着手,在分析了格尔木自然环境特征及历史人文背景的基础上,着重论述了格尔木城市特色,以及营造其城市特色的措施。  相似文献   

5.
青海省格尔木地区植物生长期短,植被退化严重、长势不良,经济树种缺乏。枸杞适应范围广,适应性较强,对土壤要求不严,耐干旱、瘠薄、盐碱、沙荒,适宜在青海格尔木地区恶劣的自然条件下栽培,有效地对该树种进行人工栽培和进一步开发利用具有重要的意义。  相似文献   

6.
中国水资源问题及其对策研究   总被引:4,自引:0,他引:4  
李茜 《科技资讯》2006,(26):192-192
水资源是基础性资源,对我国综合国力有很重要的影响。但是目前,我国水资源存在一系列的问题,如水资源时空分布不均衡水污染严重等。本文从水资源的概念入手,对中国水资源的现状及问题进行了分析,同时对我国水资源可持续发展的对策进行了探讨。  相似文献   

7.
中国区域发展的水资源压力及空间分布   总被引:3,自引:0,他引:3  
水资源压力指数可用来衡量一个国家和区域的天然水资源相对稀缺性,并判断水资源是否成为社会经济发展的障碍,水资源压力从水资源需求角度,可分为水资源数量压力,经济水资源压力和水环境压力,它们分别受人口密度,经济发展规模和经济发展潜力以及环境对水环境需求的影响,水资源综合压力为上述这些压力按一定权重的组合,本文在不同水资源压力指数计算的基础上,对全国各行政区域的综合水资源压力进行了分析。  相似文献   

8.
水资源配置的和谐性分析   总被引:13,自引:2,他引:13       下载免费PDF全文
根据水资源配置的目标和原则,提出水资源系统和谐配置的概念。给出了水资源和谐度的计算方法,运用层次评判、综合分析等方法建立水资源和谐的评判矩阵,定量分析水资源配置的和谐性。并以实例说明,可通过对水资源配置和谐性的分析,达到对水资源配置实施控制的目的。  相似文献   

9.
刁宗丽  姜德荣 《科技信息》2009,(25):384-384
水资源短缺已成为全球性问题,水资源不仅是一个生态环境问题,也是一个经济问题、社会问题,直接关系到一个地区的经济发展和社会稳定。对一些水资源紧缺的地区来说.水资源已经成为关系到生存和发展的战略问题。因此有必要对区域水资源安全问题进行分析研究,便于对区域水资源安全进行客观真实的评估。本文以滕州市为例,从水资源水量安全、水质安全方面,探讨区域水资源安全问题。  相似文献   

10.
银川平原水资源承载力的初步研究   总被引:3,自引:0,他引:3  
从水资源的概念入手,以银川平原为研究对象,对银川平原水资源自然环境、土地资源、水环境等现状进行了分析,并在构建水资源承载力评价指标体系的基础上定量分析得出银川平原水资源承载力,并对其进行评价,最后系统分析了银川平原水资源量、主要利用状况、水环境质量、区域发展对水资源的需求及水资源承载性.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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