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11.
储层预测技术已成为岩性油气藏勘探中的一项常规技术.厄瓜多尔西海岸地区蕴含着丰富的石油和天然气资源,但整个地区勘探程度相对较低,使用宽带约束地震反演技术进行储层预测是非常必要的.选择瓜亚基尔工区,使用地震纯波数据进行储层预测研究.首先进行测井曲线标准化处理,利用阻抗-伽玛交汇图分析确定储层岩石地球物理特征,然后针对目的层进行稀疏脉冲反演和储层厚度的计算,最后对反演结果和储层平面分布特征进行分析,确定有利勘探目标.预测的砂岩厚度和已钻井实测的砂岩厚度之间的误差很小,吻合较好,从而证明了该技术的有效性.  相似文献   
12.
利用宁波S波段双偏振天气雷达资料、NCEP再分析资料、结合常规观测资料和实地冰雹调查资料,对2020年3月21日浙江省中北部一次强雹暴灾害过程(简称“03·21”过程)的天气背景和双偏振雷达回波演变特征进行分析。结果表明:(1)此次雹暴过程环流形势属于低层暖平流强迫类型,雹暴影响过程约4 h,雹暴A和B先以强的对流单体形态移动,在自西向东移动过程中分别加强为超级单体。(2)典型降雹时次具有明显的三体散射特征(TBSS),垂直剖面图上强回波(>50 dBz)伸展高度超过-20℃层,低层的弱回波,中高层悬垂回波明显。径向速度垂直剖面图上,雹暴低层辐合,其上叠加了辐散层,使得雹块得以继续形成和增长。(3)冰雹区出现了ZDR冰雹信号,对应的反射率因子(ZH)均大于65 dBz,差分反射率因子(ZDR)介于-2.0~0 dB,相关系数(CC)介于0.80~0.98;当结合ZH、ZDR、CC综合判断云中有冰雹粒子,CC...  相似文献   
13.
常规声波反演的方法原理和反演技术以层状介质为基础,其研究目标多是层状储层。碳酸盐岩溶洞型储层具有非规则形态、非均匀散布的特征,常规声波反演技术有其不适应之处。笔者研究的测井约束多重反演技术,解决了非层状、非均匀储层的地震反演问题,得出反映碳酸盐岩溶洞储层信息的波阻抗数据体,提取了突出溶洞型储集体低速特征的差异波阻抗,为寻找碳酸盐岩溶洞型油气藏提供了可靠的依据。  相似文献   
14.
Measurement of Ba isotope ratios of widely available reference materials is required for interlaboratory comparison of data. Here, we present new Ba isotope data for thirty‐four geological reference materials, including silicates, carbonates, river/marine sediments and soils. These reference materials (RMs) cover a wide range of compositions, with Ba mass fractions ranging from 6.4 to 1900 µg g?1, SiO2 from 0.62% to 90.36% m/m and MgO from 0.08% to 41.03% m/m. Accuracy and precision of our data were assessed by the analyses of duplicate samples and USGS rock RMs. Barium isotopic compositions for all RMs were in agreement with each other within uncertainty. The variation of δ138/134Ba in these RMs was up to 0.7‰. The shale reference sample, affected by a high degree of chemical weathering, had the highest δ138/134Ba (0.37 ± 0.03‰), while the stream sediment obtained from a tributary draining carbonate rocks was characterised by the lowest δ138/134Ba (?0.30 ± 0.05‰). Geochemical RMs play a fundamental role in the high‐precision and accurate determination of Ba isotopic compositions for natural samples with similar matrices. Analyses of these RMs could provide universal comparability for Ba isotope data and enable assessment of accuracy for interlaboratory data.  相似文献   
15.
The high‐precision δ60/58Ni values of twenty‐six geological reference materials, including igneous rocks, sedimentary rocks, stream sediments, soils and plants are reported. The δ60/58Ni values of all samples were determined by double‐spike MC‐ICP‐MS (Nu Plasma III). Isotope standard solution (NIST SRM 986) and geological reference materials (BHVO‐2, BCR‐2, JP‐1, PCC‐1, etc.) were used to evaluate the measurement bias and intermediate precision over a period of six months. Our results show that the intermediate precision of Ni isotope determination was 0.05‰ (2s, n = 69) for spiked NIST SRM 986 and typically 0.06‰ for actual samples, and the δ60/58Ni NIST SRM 986 values were in excellent agreement with previous studies. Eighteen high‐precision Ni isotope ratios of geological reference materials are first reported here, and their δ60/58Ni values varied from ?0.27‰ to 0.52‰, with a mean of 0.13 ± 0.34‰ (2s, n = 18). Additionally, SGR‐1b (0.56 ± 0.04‰, 2s), GSS‐1 (?0.27 ± 0.06‰, 2s), GSS‐7 (?0.11 ± 0.01‰, 2s), GSD‐10 (0.46 ± 0.06‰, 2s) and GSB‐12 (0.52 ± 0.06‰, 2s) could potentially serve as candidate reference materials for Ni isotope fractionation and comparison of Ni isotopic compositions among different laboratories.  相似文献   
16.
2010年福建一次早春强降雹超级单体风暴对比分析   总被引:3,自引:0,他引:3  
利用探空、地面资料以及建阳、龙岩、长乐三部新一代天气雷达资料,对2010年3月5日福建中北部地区5cm强降雹的两个超级单体风暴进行了对比分析。结果表明,干暖盖、强垂直风切变、中高层正涡度区及地面中尺度低压为超级单体的形成提供了良好的环境场。两个超级单体都是由多单体合并后发展起来的,在成熟阶段以右移为主,属长寿命右移风暴:第一个超级单体在发展过程中由于地形作用和新单体的并入经历了3次加强过程,低层出现明显的钩状回波、中高层三体散射特征;第二个超级单体经历了多单体风暴—超级单体风暴—多单体风暴3个阶段,成熟阶段低层呈现出明显的倒"V"形回波特征,中高层有明显向右伸展的云帖。两个超级单体风暴的中气旋都是由中层发展起来,随着中气旋强度不断加强和厚度加大,最强切变中心突降时出现冰雹、大风强对流天气。通过对第一个超级单体中气旋流场分析,发现风暴前、后侧的下沉气流与低层入流形成了明显的辐合旋转作用,下沉的干冷气流进一步推动低层的暖湿入流,形成强烈的上升气流,并在风暴顶形成强辐散,使得风暴长时间维持。第二个超级单体在风暴减弱阶段,风暴右侧出现中气旋分裂,之后减弱、消失。产生强对流天气时,中高层维持高反射率因子,出现三体散射现象、风暴顶强烈辐散以及较大的VIL密度等特征。  相似文献   
17.
We present a revised method for the determination of concentrations of rare earth (REE) and other trace elements (Y, Sc, Zr, Ba, Hf, Th) in geological samples. Our analytical procedure involves sample digestion using alkaline fusion (NaOH-Na2O2) after addition of a Tm spike, co-precipitation on iron hydroxides, and measurement by sector field-inductively coupled plasma-mass spectrometry (SF-ICP-MS). The procedure was tested successfully for various rock types (i.e., basalt, ultramafic rock, sediment, soil, granite), including rocks with low trace element abundances (sub ng g−1). Results obtained for a series of nine geological reference materials (BIR-1, BCR-2, UB-N, JP-1, AC-E, MA-N, MAG-1, GSMS-2, GSS-4) are in reasonable agreement with published working values.  相似文献   
18.
We briefly describe the polarization state of the spike groups and fast fine structures superimposed on the 47GB microwave burst of 1991 May 16. At two frequencies 100 MHz apart, namely, 2645 and 2545 MHz, the polarization showed rapid reversals on short time scales of the order of 50 100ms. We think this is probably related to fluctuations on both short time and small spatial scales, in the plasma density and magnetic field of the emission region. Thése oscillations cause the plasma and cyclotron frequency ratio to vary around the value of , thus making the electron cyclotron maser instability growth rate to be dominated alternately by the X mode and the O mode and the polarization state to switch from one sign to the other.  相似文献   
19.
Isotope dilution (ID) is a widely used analytical technique to determine elemental abundance to a high degree of accuracy and precision, using a spiked isotope tracer. This technique also enables efficient correction of the inevitable phenomenon of analytical mass fractionation during mass spectrometric analysis. It is also used to determine stable isotope variations of an element in a sample relative to a reference material, using tracers enriched in two isotopes (popularly known as the double spike method). Isotope dilution data reduction can be performed in Microsoft® Excel™ using different algorithmic approaches. Additional software such as iolite and MATLAB® offer algorithm implementations to perform these calculations. These are however limited to use within particular laboratories/research groups, or either require additional cost-bound software or some degree of knowledge in computer programming languages for use, or all of these. To ease this situation, a graphical user interface-based software is proposed (here named Parmanu-Gunak, meaning Atom-Calculator in Sanskrit text) to invert both single and double spiked isotope data, with the aim of making it a standard tool for ID data reduction. Examples of Nd and Mo isotopes are used to demonstrate the robustness of the program.  相似文献   
20.
俞雪华  徐民健 《天文学报》1995,36(4):359-366
本文采用等离子体动力学方法,研究了日冕条件下磁化非相对论热等离子体对太阳射电辐射产生的电子回旋共振吸收,并在辐射频率等于电子回旋谐波频率时求得n≥2谐波吸收率的近似表示式,以及其对等离子体温度,出射角度和谐波数的变化规律,在应用部分,讨论了电子回旋共振吸收对于太阳射电尖峰爆发的影响,认为目前观测到的尖峰爆,大多数高能电子束来自日冕的内层。  相似文献   
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