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91.
Optimizing industrial structure is an important research object of human-economic geography, and it is also the object of government departments to strengthen macro-control. This has become even greater problem that China has entered the “new normal” in recent years. The study uses a multi-regional input-output model, with linear programming to build an optimal model of industrial structure as well as a model of optimization degree under the energy constraint. The results of the study revealed that: (1) the degree of optimization of industrial structure in Anhui Province is optimal (0.763), while that of Shanxi Province is the lowest (0.662); (2) the degree of optimization of industrial structure is negatively related to energy consumption per unit output value and the proportion of heavy industry; and (3) overall, central China should maintain or moderately increase the proportions of resource-based industry, greatly increase the proportions of manufacturing, including transport and telecommunications equipment, computers and other electronic equipment, and moderately reduce the proportions of smelting and pressing of metals and non-metal mineral products. In terms of service industries, the region should greatly increase the proportions of the production and supply of natural gas and tap water, moderately reduce or maintain the proportions of transport and storage as well as tourism, and maintain or moderately reduce the proportions of wholesale trade, retail trade and catering services.  相似文献   
92.
金融危机前后基于垂直专业化的中国出口价值份额分析   总被引:2,自引:1,他引:1  
唐志鹏  宋涛 《地理科学》2016,36(8):1148-1154
2008年全球金融危机使中国出口增速放缓,也给中国提升出口贸易的质量效益带来了机会。利用2007年和2010年中国30省区市区域间投入产出表计算了中国和省域以及国外在中国出口中分享的单位出口价值份额。研究结果发现,金融危机后在中国单位出口中,全国分享的经济收益整体有所提升,进一步从省域格局来看,分享中国单位出口经济收益较高的省域主要分布在东部沿海地区,而从出口部门来看,全国带有技术含量的制造业分享的经济收益在2007~2010年增长最多,而依赖资源和劳动力投入的低端产品制造分享的经济收益下降最多,沿海出口大省仍然是分享制造业出口价值份额最主要的地区,地理区位依旧是出口贸易最有利的条件之一。尽快淘汰落后产能,推动产业升级转型,加大科技含量,才能促使“中国制造”尽快完成向“中国智造”转变。  相似文献   
93.
甄别生源要素参与的海洋沉积物矿化过程对探析生源要素的生物地球化学循环有重要的作用,矿化作用包括有氧呼吸、硝酸盐还原、铁锰异化还原及硫酸盐还原等多个过程,但如何区分这些过程一直是海洋沉积物矿化研究的难点。本研究采用气相色谱-质谱(GC-MS)联用对热带西太平洋沉积物中的磷脂脂肪酸(phospholipid fatty acid, PLFA)的组成进行了解析,并分析不同矿化过程中的主要PLFA种类及其影响因素,探究PLFA对沉积物矿化的指示作用。结果表明,PLFA总量在有氧呼吸过程中最高,而在硝酸盐还原过程中最低;且14:0、i14:0、i15:0和i19:0是有氧呼吸过程中微生物PLFA的主要组成,当其含量明显降低时可以指示沉积物矿化从有氧呼吸转变为硝酸盐还原;而10:0、17:0、20:0和22:0含量之和显著增加时则指示了硫酸盐还原过程的发生。在热带西太平洋沉积物中,总有机碳(TOC)和总有机氮(TON)含量以及间隙水NO3-N含量是PLFA含量的重要影响因素,PLFA总量随着TOC和TON含量的减少而减少,并且TOC和TON的降解能够促进PLFA降解的发生,对PLFA组成有更直接的影响。  相似文献   
94.
Located at the northwest continental slope of the South China Sea, the Qiongdongnan Basin bears valley-shaped bathymetry deepening toward east. It is separated from the Yinggehai Basin through NW-trend...  相似文献   
95.
琼东南盆地井震地层对比分析及区域地层格架的建立   总被引:3,自引:3,他引:0  
琼东南盆地历经断陷、断坳、裂后热沉降和裂后加速沉降等一系列的构造变动,沉积环境由始新世的滨海环境发展为现今的深水环境,形成了一套包括滨岸沉积、滨浅海沉积、陆架和陆坡沉积、以及半深海沉积的地层组合,具有良好的油气资源的生储盖条件,已成为当前油气资源勘探开发的重点区域。本文首先对盆地区域内钻井和地震剖面进行了主要地层界面(T20、T30、T40、T50、T60和T70)的识别和提取(点),继而结合连井地震剖面(线)和盆地区域过井地震剖面(面)对主要地层界面做了追踪对比分析,再依据古生物年代,建立了适用于琼东南盆地的区域地层年代格架。在琼东南盆地浅水区主要沉积了新近系地层(T60-T20),断裂基本不发育,地层厚度变化不大,极少有明显的上超和削截,局部地区发育有利于油气储集的三角洲沉积体系,表明琼东南盆地新近纪时期受构造作用影响较小。在深水区,新近系地层(T60-T20)和浅水区特征相似,仅反射特征有所不同;古近系地层(T100-T60)内部层序结构主要为楔状或近平行状,具有明显的上超和削截,地层厚度较大,断裂明显并导致地层错断,表明琼东南盆地深水区在古近纪时期主要受构造作用控制,并伴随着强烈的拉张和快速沉降作用,沉积环境主要为浅海。在近东西向的中央峡谷内存在有三期砂体:第一期砂体(井深3 528~3 336m,厚约192m)形成于距今11.6~5.5Ma(T40-T30),分布范围跨越中央峡谷的陵水-松南-宝岛段,沉积物构成包括浊积水道沉积、浊积席状砂、块体流沉积、深海泥质沉积、天然堤及漫溢沉积等;第二期砂体(井深4 100~3 900m,厚约200m)形成于距今5.5~4.2Ma(T30-T29),分布范围跨越中央峡谷的乐东-陵水段,以重力流沉积为主;第三期砂体(深度3 630~3 400m,厚约230m)发育于距今4.2~3.6Ma(T29-T28),分布于峡谷的乐东-莺东段,以浊积水道沉积为主。三期砂体在琼东南盆地中央坳陷带自东向西、由老到新依次展布,构成了良好的油气储层体。  相似文献   
96.
This paper aims to evaluate the effects of ultraviolet-Bradiation(UVBR) on Gracilaria lemaneiformis,a commercial red macroalga and an important source of agar. To study the in-vitro effect of UVBR on G. lemaneiformis,this plant was cultivated and exposed to photosynthetically active radiation(PAR) at 40 μmol photons/(m2 ·s) and enhanced UVBR(0,0.36,0.72,1.08,1.44,and 1.80 k J/(m 2 ·d)) for 13 days. The samples were processed for histochemical analysis,and the growth rate,photosynthetic pigment contents,photosynthetic performance,reactive oxygen species levels,membrane permeability,malonyl dialdehyde contents and antioxidant capacity of G. lemaneiformis were investigated. After 13 days of exposure to PAR+UVBR,G. lemaneiformis showed photodamage and photoinhibition of photosynthetic pigments(chlorophylla and phycoerythrin),leading to a decreased photosynthetic efficiency. Further,there was a corresponding decrease in the relative growth rates and depigmentation and partial necrosis of the apical segments were noted after exposure to PAR+UVBR. Additionally,UVBR induced excess production of superoxide radicals and hydrogen peroxide,eliciting a marked cellular membrane damage and antioxidative response.  相似文献   
97.
Industrial wastewater discharge in China is increasing with the country′s economic development and it is worthy of concern. The discharge is primarily relevant to the direct discharge coefficient of each sector of the economy, its direct input coefficient and the final demand in input-output models. In this study, we calculated the sensitivity of the reduction in the Chinese industrial wastewater discharge using the direct input coefficients based on the theory of error-transmission in an input-output framework. Using input-output models, we calculated the direct and total industrial wastewater discharge coefficients. Analysis of 2007 input-output data of 30 sectors of the Chinese economy and of 30 provincial regions of China indicates that by lowering their direct input coefficients, the manufacturers of textiles, paper and paper products, chemical products, smelting and metal pressing, telecommunication equipment, computers and other electronic equipment will significantly reduce their amounts of industrial wastewater discharge. By lowering intra-provincial direct input coefficients to industrial sectors themselves of Jiangsu, Shandong and Zhejiang, there will be a significant reduction in industrial wastewater discharge for the country as a whole. Investment in production technology and improvement in organizational efficiency in these sectors and in these provinces can help lessen the direct input coefficients, thereby effectively achieving a reduction in industrial wastewater discharge in China via industrial restructuring.  相似文献   
98.
In this paper, the spatial distribution and source of the PCBs in surface sediments of the Southern Yellow Sea (SYS) and influencing factors, such as the sediment characteristics (components, relative proportions and total organic carbon contents), and hydrodynamic conditions were analyzed. PCB concentrations in the surface sediments ranged from 518-5848 pg/g, with average values of 1715 pg/g decreasing sharply compared to last year. In the study area, the PCB pollution level in the middle area was the highest, followed by that of the east coast and the west coast, respectively. Although the PCB level in the coastal areas was lower than that in the middle areas, it was proven in our study that the Yellow Sea obtained PCBs by virtue of river inputs. There was a positive and pertinent correlation between the clay proportion and PCB concentrations, and the increase of the PCB concentrations was directly proportional to the increase of TOC contents, with r=0.61, but it was contrary to the sediment grain size. Consequently, the factors controlling PCB distribution had direct or indirect relationships with sediment grain size; moreover, the hydrodynamic conditions determined the sediment components and grain size. In conclusion, hydrodynamic conditions of the Yellow Sea were the most important influencing factors effecting the distribution of PCBs in the surface sediments of the SYS.  相似文献   
99.
本文根据断层的力学性质、活动习性、褶皱、断陷盆地、平原、海湾的形成机理,火山活动、水系分布格局,震源机制解、地壳形变场、GPS观测成果和EDM(光电测距)资料等,对比研究了台湾海峡及其两岸现今的地球动力学环境。结果表明:台湾海峡处在北西方向引张的应力环境;台湾地区受到来自太平洋菲律宾海板块向北西方向的挤压和因台湾海峡下降而产生的向南东方向的挤压;福建沿海则受到印度板块向北向东的挤压和太平洋菲律宾海板块向北西方向的挤压以及台湾海峡下降而产生的向北西方向的挤压。  相似文献   
100.
全面分析重力测量的各种误差和目前能达到的精度后,对垂直形变监测中引入重力观测值的可行性进行了具体研究。结果表明,若仅是为了测定点的垂直位移的高程速率,增加重力测量数据后对形变分析的精度增益十分有限。但是对于大跨度垂直形变监测和局部地区突发性垂直形变测定,重力测量方法可以及时掌握垂直形变的趋势  相似文献   
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