查询词典 isotope

The result of factor analysis can provide the changes of relative precipitation and temperature variations. In trace elements, Cu, As, Zn, Pb and Ni were apparently enrichmented in soil layers and are sensitive to climatic changes. Carbon isotope is more sensitive to climatic changes than that of oxygen isotope in loess stratigraphy. The heavy mineral are varified in the loess stratigraphy, but their content differences between loess and palaeosol is little. Though the palynologic analyses results reveal that pollens and spores are fewer in the loess stratigraphy, they differ greatly in loess layer and palaeosol layer not only in species but also in types, i. e., the pollens and spores indicating warm and moist climate, such as Lles, Podocarpus, Polopydium, Pteris grerilliana Wall, Pterocarya and Juglans appear in palaeosol layers, while those indicating cold and dry climate such as Ephedra, Artemisia, Chinopodiaceae, Picea and Abies exist mainly in loess layers. The pollen content of broad-leaved tree mainly consisting of Pterocarya is up to 60% in palaeosol 〓, while the content of Ephedra is more than 50% in 〓 loess layer, showing that the environment differed greatly when 〓 and 〓 were formed.

当然，常量元素氧化物的组合因子分析结果可提供相对降水与相对温度在剖面的变化，因而来反映气候状况更为理想；微量元素中Cu、As、Zn、Pb与Ni在成土过程中富集明显，亦较好地反映了气候变化；稳定同位素中的碳同位素比氧同位素更能敏感记录气候的变化；研究区黄土地层中重矿物种类较多，但黄土层与古土壤层中含量差异不大；孢粉分析结果揭示，尽管研究区黄土层中孢粉总量相对较为贫乏，但黄土层与古土壤层中孢粉种属相差较大：在古土壤层内出现了指示相对暖湿环境的冬青属、罗汉松属、水龙骨属、林下凤尾蕨、枫杨、胡桃等植物孢粉，而黄土层中麻黄、藜科、蒿属及冷杉、云杉含量较高。

The feature of oxygen isotope for magnetite from Abagong iron deposit reflects that the water in the fluid of mineralization resides in the initial magma, implying the magma genesis of mineralization. The similaritary features of REE and trace elements for coexisting apatite with magnetite in the Abagong, the Kiruna type and the Ninwu porphyrite iron deposit show their common genesis, indicating that Abagong iron deposit resulted from the intrusion of late ore magma due to the magma differentiation. The characteristic of sulfur isotope composition implies that the Abagong iron deposit resides in basaltic magma from mantle resource.

阿巴宫铁矿磁铁矿氧同位素特征反映了成矿流体中水来源于原始岩浆水，暗示该铁矿的岩浆成因；与磁铁矿共生的磷灰石稀土和微量元素特征与Kiruna型铁矿以及宁芜玢岩铁矿中磷灰石特征非常相似，表明它们具有相同的成因机理，反映出阿巴宫铁矿为岩浆分异的晚期矿浆贯入式成因；其硫同位素特征表明成矿物质源自幔源的玄武质岩浆。

Using GC/C/MS on-line carbon isotope analysis technique, we obtained the stable carbon isotope ratios of n-alkanes, iso-alkanes from the light hydrocarbon compositions and pristane, phytane in crude oils in Tarim basin.

本文利用新兴的原油单体烃类在线同位素分析技术测定了塔里木盆地原油及凝析油的正构烷烃、轻烃部分的异构烷烃和植烷、姥鲛烷的稳定碳同位素值。

Distinguish by using a radioactive isotope or an isotope of unusual mass for tracing through chemical reactions.

用放射性同位素或不寻常质量的同位素使元素或原子显示运动踪迹。

The calculated results show that the CaI vibrational population peaks moved to low value.The calculated cross-section changed slightness duo to isotope effect. The angle product distributions tend to backward scattering also and isotope effect is not observably. Thecalculated

由于同位素效应的影响，产物Cal的振动态分布向低振动态转移；反应体系的散射截面在低碰撞能和高碰撞能处有些微变化；受到反应物质量因子变化的影响，转动取向值减少，产物转达取向强烈；产物的角分布同位素效应不明显。

The current study and C and O isotope evolution are consistent with the previous research results, which provides isotopic evidence supporting the existence of an aulacogen basin alone, and furthermore are highly concordant with the C and O isotope evolutions in Belt Supergroup in North America and MidRiphean in Ural, Russia, which suggests a response to a global paleoocean geochemical setting.

研究区与天津蓟县和北京十三陵地区的中、新元古代碳酸盐岩碳、氧同位素组成与演化表现出明显的相似性，反映了它们共同受燕山裂陷槽发育的控制；同时，与北美Belt超群和俄罗斯乌拉尔里菲期碳酸盐岩碳、氧同位素组成、演变的高度协同性，又说明了中、新元古代碳酸盐岩中碳、氧同位素组成、演化响应于全球古海洋背景和地球化学条件。

E. , the middle Devonian sedimentary event, which sedimented a suite of epicontinental -coasta1 paraf1ysch formation (the litholcgy was consisted of low fractoin feldspare sandstone and siltstone, and a layer of argilliferous limestone); secondly, the late Variscan magmatic-tectonic event , three biotite diorite batholiths ( previous K-Ar model isotope age was about 220～260Ma and our two -stage common lead isotope age was 260+ 70Ma) and a large number of fracture-controlled quartz diorite veins intrude, and a series of NS distributed tightly complex folds and fractures were developed; thirdly, the late Paleozoic very 1ow grade metamorphism- deformation event, the chlorite-illite crystallinity indices (Δ°2θ) XRD measurements were about 0.25～0.29, which was correlated to the lower part of the anchimetamorphism, and the extremely dense schists were developed throughout the district outcrops

相当于近变质带的下部，并形成切穿矿区几乎所有主要地质体的窃集片理，这与有限相系浅变质碎屑岩的基本宏观地质特征相吻合

The study indicates that the Pb and Zn ore-forming elements probably come from the basement rocks; The initial Pb isotope could be derived from the crust-mantle mixing in the erogenic belt; sulfur isotope composition is enriched in heavy sulfur that may have come from the seawater sulfate in the synchronous sedimentation; the ore is characterized with REE enrichment, obvious fractionation of LREE and flat-pattern of HREE; ore-forming media is thermal brine fluid; both mineralization temperature and pressure are low; the metallogenic epoch is probably in late Dengying epoch of Sinian period.

研究表明，基底岩系可能为成矿元素Pb、Zn的主要来源；原始铅主要来源于壳幔棍合的造山带；硫同位素富集重硫，可能主要来源海水硫酸盐；矿石中稀土元素富集，轻稀土分异较明显，而重稀土分异不明显；成矿流体推测为热卤水性质，成矿温度为中低温，具有低压浅成成矿特点；矿床形成的初期应始于震旦纪灯影世晚期。

There was enrichment of the heavier isotope of mesoplankton with increasing grain size, showing carbon isotope enrichment along trophic levels.

中型浮游动物随粒径的增大，其δ13C值增大，显示出营养层次的碳同位素富集作用，但不同粒级组分相互间δ13C值也存在着相当程度的重叠，实际上这也是其生物组分有重叠的反映。

Three hypotheses is put forward, based on microexamination about sample evaporation during determaination of isotope abundance by thermal ionization:1. Only atoms uncovered by outer layer atoms can be vapoured; 2. Atoms covered by outer layer atoms can diffuse but cannot vapoure; 3. The probability of diffusion of isotope atoms is in direct proportion to its probability of evaporation.

根据对热表面电离源同位素丰度测量过程中样品蒸发的微观研究，提出如下三条假设：(1 )未被外层原子覆盖的原子才能蒸发；(2 )被外层原子覆盖的原子只能扩散不能蒸发；(3 )同位素原子的扩散几率与蒸发几率成正比。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。