查询词典 isotopic

They would leave subtle clues in the isotopic composition of the limestone by shifting the ratios of light to heavy carbon and oxygen atoms in its calcium carbonate.

那样会在石灰岩的同位素构成中留下多多少少的痕迹——碳酸钙中碳原子和氧原子的轻重比例会改变。

They would leave subtle clues in the isotopic composition of the limestone by shifting the ratios of light to heavy carbon and oxygen atoms in its calcium carbonate.

因为如果是那样的话，阳光将会被转换成大量的碳、氧原子保存到石灰岩中的碳酸钙里，而事实却是，岩层的同位素组成中没有留下任何蛛丝马迹。

Such features are typical of ancient lower continental crust, e.g., Archean granulite terranes that experienced extensive U-Th loss and developed time-integrated low radiogenic Pb compositions. The occurrence of the west Ujimqin andesites indicates the existence of ancient continental lower crust beneath the NE China fold belt.4 The Mesozoic granitoids in the Zhangguangcai Range and Jiamusi block have lower Nd ε_(Nd =-3.5～+ 2.1, T_ = 1.0～1.27Ga and highly radiogenic Pb and Sr isotopic composition ~(206Pb/~(204)Pb = 18.4～18.9,~(87)Sr/~(86)Sr = 0.705～0.711, suggesting that the pelagic sediments of the Paleo-Asian Ocean or their metamorphosed derivates were an important component in the region.5 The Pb isotope mapping results show that the mafic rocks in the northern Hinggan Mountains have higher and weakly variable ~(206)Pb/~(204)Pb ratios than those from the southern Hinggan Mountains and the Liaoyuan-Yanji area.

该套岩石的出现为证明东北地区存在古老大陆下地壳提供了重要证据。4张广才岭-佳木斯地区中生代花岗岩表现出低ε_(-3.5～+2.1)、高T_(1.0～1.27Ga)和高放射成因Sr~(87Sr/~(86)Sr=0.705～0.711和Pb同位素组成~(206Pb/~(204)Pb=18.4～18.9，反映了古亚洲洋远洋沉积物或变沉积岩为区域地壳的重要组分之一。5同位素填图结果表明，大兴安岭北区基性火山岩表现出较高且变化小的~(206)Pb/~(204)Pb比值；而南兴安岭-辽源-延吉地区中生代基性火山岩整体上表现出相对北区低~(206)Pb/~(204)Pb同位素比值特征。

The 40Ar/39Ar isotopic dating of amphiboles collected from different depths of core samples in No. 3 intrusion gave a (228.2±3.0) Ma plateau age and a (230.1±7.1) Ma isochron age.

本次工作对采自不同深度岩心样品中的单矿物角闪石进行40Ar/39Ar同位素年代学研究，得到(228.2±3.0)Ma的坪年龄和(230.1±7.1)Ma的等时线年龄。

The chemical and isotopic arrays formed by basalts indicate mixing of components from two distinct source regions.

玄武岩所形成的化学和同位素阵列表明，它们是由来源于2个不同源区的组分混合产生的。

REE abundances and Sr and Nd isotopic composition in mantle xenoliths from basalts in Hannuoba are reported in this paper.

本文报道汉诺坝玄武岩中地幔岩捕掳体的REE丰度和Sr、Nd同位素组成。

That is to say, the Cenozoic alkaline basalts were more or less modified by some enriched Sr-Nd isotopic components during their eruption.

同时，拉斑玄武岩不是碱性玄武质岩浆直接结晶分异的产物，亦不是完全由部分熔融程度的不同造成的。

The isotopic abundances of rare gases and cosmic-ray exposure ages of asteroid meteorites, planetary meteorites and the Apollo lunar samples applied to clue up and understanding cosmic-ray exposure history of parent bodies of different meteorite types, collision events, the relationship between cosmic-ray exposure ages and heliocentric distance of the parent bodies, irradiation history of precompaction exposure of chondrules, pairing meteorites for the Antarctic meteorites and desert meteorites, the ejection history of planetary meteorites, and relative ages of lunar craters and so on.

小行星陨石、行星陨石及阿波罗月球样品的稀有气体同位素丰度和宇宙射线暴露年龄，已广泛应用于探索和了解不同类型陨石母体的宇宙射线暴露历史、冲击碰撞事件、暴露年龄与日心距离的关系、吸积形成母体前硅酸盐球粒的辐照历史、南极和沙漠陨石中成对陨石的判别、行星陨石的溅射历史及月坑的相对年龄等关键词：宇宙射线暴露年龄；陨石；球粒陨石；无球粒陨石；火星陨石；中铁陨石

The geologists have attached much importance to the particularity of ReOs isotopic system and its application is getting popular. The author sums up and compares several kinds of sample digestion methods for ReOs isotope analysis (NiS fire assay, Carius tube digestion, high pressure asher, leaching, and water disposing), the procedures of separating Os ( conventional distillation, liquid Br2 and CCl4 or CHCl3 extraction, rapid extraction with low blank, minitype distillation) and purifying Os, improved mass spectrometry measurement of Os isotope and its application progress in the earth science research brought along the improved measuring method.

总结和对比了近年来ReOs同位素分析中样品分解的不同方法（NiS火试金法、Carius管溶样法、高压灰化消解法、浸提法、水样处理法）、Os的分离（常规蒸馏、液溴和CCl4提取、快速低本底提取、小型蒸馏）与纯化流程、Os同位素比值质谱测定法（NTIMS、ICPMS、微区原位分析）及随测定方法的改进ReOs同位素体系在地球科学研究中的应用进展。

The geochemical characteristics of the adsorbed gas in sample log verified that fault do play an important role for gas migration. The fault activity coincided with the isotopic composition of the adsorbed gas.

依据录井天然气的同位素特征和流体包裹体的分析证实了断裂是本区天然气垂向运移的主要通道，断层的活动与罐装岩屑录井气地球化学特征完全一致。

Through comparing with the results by simulation to study the effects of theprojectile"s final velocity, the angle of rotation and the ballistic trajectory"s migration withdifferent projectile"s rotating speeds, different target"s moving speeds and differentpenetration angles.

通过比较数值模拟的结果来研究不同弹头转速、目标速度、侵彻角对侵彻过程中弹头最终速度、翻转角度和弹道偏移的影响。

I love stationery and all the accoutrement of writing.

我爱文具以及所有的书写的工具装备。