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101.
采用积分安培-离子色谱法同时测定地下水中的溴离子和碘离子,该方法的相关性好( r>0.999),精密度高(RSD%<4.0),样品加标回收率为90~110%,溴离子检出限为5.6μg/L ,碘离子检出限为2.1μg/L。本法简便、快速、准确且选择性好,可用于分析地下水中的溴离子和碘离子。 相似文献
102.
以五氧化二钒和三氧化二铋为熔剂,研究了分离富集痕量碘的最佳条性,以及影响催化反应速度的因素。用改变温度和时间的方法提高测定方法的灵敏度和扩大碘的测定范围。本方法具有灵敏度高、选择性好、操作简便、快速和经济的特点,最低检出限为0.033ppm碘,标准偏差为4.45%。 相似文献
103.
生物样品用艾斯卡熔剂分解,强酸性阳离子交换树脂静态吸附分离大量Na^+等阳离子后,采用Fe^3+-SCN^--NO2^-催化体系分光光度法测定痕量碘。通过正交实验确定了催化反应的最佳实验条件。方法检出限(6s)为0.13μg/g,方法精密度(RSD,n=12)为3.69%~8.28%。用国家一级生物标准物质进行验证,测定值与标准值相符。 相似文献
104.
In the present paper, iodine(I), iron(Fe), manganese(Mn), cobalt(Co), phosphorus(P) and calcium(Ca)contents in three ferromanganese crusts from the Pacific Ocean are measured by spectrophotometric method and inductively coupled plasma atomic emission spectrometers(ICP-AES) to investigate the contents and distribution of iodine in ferromanganese crusts. The results show that iodine contents in three crusts vary between 27.1 and 836 mg/kg, with an average of 172 mg/kg, and the profile of iodine in the three crusts all exhibits a two-stage distribution zone: a young non-phosphatized zone and an old phosphatized zone that is rich in I, P and Ca. The iodine content ratios of old to young zone in MP5D44, CXD62–1 and CXD08–1 are 2.3, 3.4 and 13.7, respectively.The boundary depths of two-stage zone in MP5D44, CXD62–1 and CXD08–1 locate at 4.0 cm, 2.5 cm and 3.75 cm,respectively, and the time of iodine mutation in three crusts ranges from 17–37 Ma derived from 129 I dating and Co empirical formula, which is consistent with the times of Cenozoic phosphatization events. The present study shows that the intensity of phosphatization is the main responsible for the distribution pattern of iodine in the crusts on the basis of the correlation analysis. Consequently, iodine is a sensitive indicator for phosphatization. 相似文献
105.
Peng He Zheng Yang Hongying Pang Ala Aldahan Xiaolin Hou G?ran Possnert Xiangjun Pei Yi Huang 《海洋学报(英文版)》2022,41(11):73-80
The English Channel (the Channel) represents a major sink and transport pathway of anthropogenic radioactive 129I. Despite this important role, data concerning the distribution of 129I in seawater of the Channel are scarce, and most of existing data are restricted to the eastern part of the Channel. The advection and dispersion of 129I from the French coast toward the central and further the English coast, especially in the Channel west of Cap de La Hague, are not fully investigated. We present results of iodine isotopes (127I and 129I) analyses of surface water samples collected along the central English Channel in October, 2010. The data show high 129I concentrations between Dover Strait and La Hague, followed by a dramatic drop towards the Celtic Sea and reveal the dispersal of 129I towards central and northern part of the Channel. Our observation also implies that the entire British coast is contaminated by 129I. 129I levels in the westernmost English Channel, close to the English coast, may reflect combined influences from La Hague and Sellafield. Evolution of 129I between 2005 and 2010 suggests a strong link to temporal marine discharges from La Hague plant. The discharges from the nuclear reprocessing facility have continued since 2010 and thus an ecological evaluation of 129I radioactive hazards in the environment of the Channel may be needed. 相似文献
106.
沉积盆地卤水来源的非传统同位素示踪研究进展 总被引:1,自引:0,他引:1
世界上大多数的沉积盆地内,在结晶基底或者沉积地层内都有矿化度较高的卤水,由于这些卤水通常携带或富含有钾、硼、锂、溴、碘、铷、铯、稀有气体及重金属元素,因此,它们是地学界的研究热点之一。随着测试技术的不断进步,非传统同位素的应用也日益广泛,但在沉积盆地卤水来源和演化方面的研究还十分薄弱,对卤水的来源和演化也还存在争议。文章回顾了硼、锂、碘和惰性气体氦、氩同位素在卤水来源研究方面的进展,并指出由于单一同位素在解释上的片面性,多种同位素相结合的示踪方法研究沉积盆地卤水的来源是国际趋势。 相似文献
107.
单扫描极谱法测定饮料和食盐中的碘 总被引:2,自引:0,他引:2
本文提出以KMnO4-NaClO作氧化剂,将碘化物氧化成碘酸盐,然后Na2SO3还原过量氧化剂,在硼砂缓冲介质中,于-1.26V测定IO^-3产生的吸附波。此体系灵敏,稳定,重现性好,线性宽,有很好的实用性。本法用于饮料和食盐中痕量碘的测定,结果满意。 相似文献
108.
The dissolved iodate and iodide distribution in the South Atlantic from the Weddell Sea to Brazil 总被引:1,自引:0,他引:1
Iodide and iodate concentrations are reported and discussed for the WOCE A23 transect from the Weddell Sea north to about 25°S. Iodide concentrations are very low in the surface waters of the Weddell Sea (20 nM) and increase steadily northwards to about 100 nM in the surface waters of the south Atlantic gyre. In deep waters iodide concentrations are low but detectable at 0.5–2 nM. There is no detectable total iodine depletion in the surface waters south of the polar front although there is a small depletion evident north of the front. The results are discussed in terms of the hydrography, nutrient concentrations and phytoplankton activity along the transect. In particular, a systematic change in the relationship between iodide and nitrate along the transect is discussed. 相似文献