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761.
基于随机有限断层法的地震烈度计算研究 总被引:1,自引:0,他引:1
采用基于动力学拐角频率的随机有限断层法,首先模拟计算了东台、如皋及大丰3个台站记录的2006年江苏东台3.8级地震的地震动,并与其实际记录进行比较研究,验证了该方法的计算结果能够较好地反映出江苏地区主震剪切波的主要特征。随后运用该方法模拟计算了1979年江苏溧阳6.0级地震震源区内156个虚拟观测点的地震动,并通过内插值的方式得到此次地震的加速度场分布情况;随后依据峰值加速度统计方法和模糊评定方法,分别计算此次地震的理论烈度分布,结果显示:两种烈度划分方法的结果与实际调查的烈度分布都基本一致,但模糊评定方法的划分结果更加接近真实的烈度分布。 相似文献
762.
分析目前多极距测量系统存在的问题,将CAN总线技术应用于多极距地电阻率测量系统中,研制基于CAN总线技术的新型电极控制器。详细介绍电极控制器的主要特点、工作原理、硬件结构设计以及通信协议。经过各种性能测试,结果表明,该电极控制器稳定可靠,符合多极距地电阻率观测要求。 相似文献
763.
A New Data Processing Strategy for Huge GNSS Global Networks 总被引:2,自引:4,他引:2
In Global Positioning System (GPS) data analyses, large networks are usually divided into sub-networks to solve the conflict between increasing amounts of data and limited computer resources, although an integrated analysis would provide better results. This conflict becomes even more critical with the increasing number of stations, and low-Earth-orbiting satellites and the Galileo system coming into operation. The major reason is that a huge number of ambiguity parameters are kept in the normal equation for sequential integer ambiguity fixing. In this paper, the problem is solved by a special procedure of parameter elimination for both real-valued and ambiguity-fixed solutions, based on an adapted ambiguity-fixing approach where the covariance-matrix of ambiguity parameters is not required anymore. It is demonstrated that, with the new strategy, the required memory can be reduced to one-tenth and the computation time to at least one-third compared to the existing methods, and huge GPS networks with several hundred stations can be processed efficiently on a personal computer. 相似文献
764.
Archaeal and bacterial glycerol dialkyl glycerol tetraethers (GDGTs) play a unique role in discerning the biogeochemical processes and climate change in terrestrial (e.g. soil, peat, stalagmites, lakes, rivers, hot springs) and marine environments. Organic proxies based on GDGTs (e.g. TEX86, MBT/CBT and BIT) have made impressive applications in the open ocean and terrestrial environments. However, the applicability of these proxies in marginal seas has not been thoroughly evaluated, which is necessary given the complexity and dynamics of these systems, such as organic matter (OM) flux, hydrodynamic conditions, and human impact. This review aims to summarize recent studies of GDGTs and GDGT-based proxies in the Chinese marginal seas (CMS), which are characterized by diverse gradient in terrigenous supplies and ocean productivity and hold rich information on climate and sea level changes, ocean current dynamics, sedimentary evolution and biogeochemical processes. 相似文献
765.
The tilt-depth method can be used to make fast estimation of the top depth of magnetic bodies. However, it is unable to estimate bottom depths and its every inversion point only has a single solution. In order to resolve such weaknesses, this paper presents an improved tilt-depth method based on the magnetic anomaly expression of vertical contact with a finite depth extent, which can simultaneously estimate top and bottom depths of magnetic bodies. In addition, multiple characteristic points are selected on the tilt angle map for joint computation to improve reliability of inversion solutions. Two- and threedimensional model tests show that this improved tilt-depth method is effective in inverting buried depths of top and bottom bodies, and has a higher inversion precision for top depths than the conventional method. The improved method is then used to process aeromagnetic data over the Changling Fault Depression in the Songliao Basin, and inversion results of top depths are found to be more accurate for actual top depths of volcanic rocks in two nearby drilled wells than those using the conventional tilt-depth method. 相似文献
766.
767.
The study of waters ecosystem and their population carrying capacity demonstrates the role of these ecosystems in economic and social development and provides a theoretical basis for the management and allocation of aquatic ecosystems. In this study, the concept of waters ecosystem population carrying capacity was defined and developmental trends in the population carrying capacity of waters ecosystem in China were evaluated. Results show that waters ecosystem population carrying capacity in China increased from 0.176×109 person year-1 in 2000 to 0.255 ×109 person year-1 in 2010; the population carrying capacity of the standard sea remained at 0.2-0.3 person ha-1; and the standard inland waters population carrying capacity increased from 1.8 to 3.2 person ha-1. This analysis indicates notable regional difference in waters population carrying capacity. In southeastern coastal China and Yangtze River drainage areas where inland waters are widely distributed and aquaculture is developed, the population carrying capacity is higher; however, in northwest China where water resource are deficient and the distribution is relatively small, the waters population carrying capacity is low. The waters ecosystem population carrying capacity of China in 2030 was predicted and results indicate strong potential for increasing waters population carrying capacity. 相似文献
768.
位于现今大陆斜坡之上的长昌—鹤山凹陷是继中国南海北部白云和荔湾深水区油气勘探突破之后的又一个深水战略性勘探区块。根据地震反射上超、下超和顶超等典型反射终止关系、地震相组合以及旋回特征,将渐新统珠海组自下向上划分为ZHSQ1—ZHSQ6共6套三级层序,并在层序格架中,识别出陆架弱—中振幅高连续席状、陆架斜坡变振幅中连续S型—斜交前积楔形、盆地斜坡变振幅中连续丘形双向上超等6种地震相类型,其中大型斜交S型前积和陆坡丘形双向超覆地震反射分别代表陆架边缘三角洲和深水扇沉积。研究表明,随着构造活动、海平面等地质条件的变化,陆架边缘三角洲及深水扇发育特征发生了相应变化。在珠海组ZHSQ1和ZHSQ2沉积时期,断层继承性活动,陆架坡折类型为断控型,沉积体系以局限浅海和近源的三角洲沉积组合为特征。在珠海组ZHSQ3—ZHSQ6沉积时期,盆地进入拗陷阶段,陆架坡折类型为沉积型坡折;在古珠江稳定充裕的供源作用下,陆架坡折带不断向海迁移且范围逐渐变大;伴随着相对海平面下降,大套的前积体不断向前推进,最大前积距离近20,km,且前积角度不断增大;同期深水扇自下而上出现频率增高,且位置更靠近陆架边缘三角洲,规模变大。 相似文献
769.
770.
对从湛江市水产品批发市场分离得到一株溶藻弧菌噬菌体的生理特性进行测定,结果表明:该株噬菌体噬菌斑12 h直径为1~1.5 mm,对紫外线敏感,暴露在紫外灯(20 W,30 cm)下30 min可丧失全部裂解活性;在pH8~11范围内裂解活性较强,最适pH值为11,裂解周期为65 min,对65℃以上的高温敏感,对乙醚和氯仿有较好的耐受性,对抗病毒药物阿昔洛韦敏感,最大常规稀释度为106CFU/mL,最佳感染复数为10。 相似文献