同位素

This paper deals with the advance in the study of terrestrial Permian-Triassic boundary. At first, some index TPTB sections and their research backgrounds are introduced. Then, the research status on the synthesis of the TPTB, including biostratigraphy, eventostratigraphy, isotopic dating, magnetostratigraphy and sequence stratigraphy etc., is analyzed. Finally, the existing problems and the next research directions about the TPTB study are assessed.

着重介绍了几个目前陆相二叠系－三叠系界线研究的重点剖面及其生物地层学研究进展；分析了陆相二叠系－三叠系界线综合地层学研究现状，包括生物地层学、事件地层学、同位素年代学、磁性地层学和层序地层学等；剖析了陆相二叠系－三叠系界线地层学研究中存在的问题及进一步的研究方向。

This paper systematically describes the Lower Triassic stratigraphic sequence of the section and summarizes the up-to-date achievements in the lithostratigraphy, biostratigraphy, magnetostratigraphy, carbon and oxygen isotopes stratigraphy, and cyclostratigraphy.

系统记述了该剖面的地层序列，包括岩石地层、生物地层、磁性地层、碳氧同位素地层和旋回地层等方面的最新研究成果。

And furthermore basing on the marks of biostratigraphy and chronostratigraphy and relatively reliable isotopic age of the 14 3rd-order sequences associated with time-space match relation of biostratigraphy and sedimental system, the formed time limits of the 3rd-order sequences is calculated primarily as 1.5-3Ma, mainly appearing at 2Ma.

进而，结合生物地层及沉积体系的时空匹配关系等多方面的综合分析，对14次三级海平面升降事件的生物地层和年代地层的标识和参考已发表的同位素年龄数据，初步估算出三级层序的形成时限为1.5-3Ma，集中出现在2Ma。

Based on the PTB study situation of the studied area, two terrestrial sections and one marine-terrestrial section were chosen for the sedimentary and sequence stratigraphy study. The former are Chahe section and Zhejue section in Weining, Guizhou, and the latter is Mide section in Xuanwei, Yunnan. The definition and correlation of the TPTB were discussed based on the results of biostratigraphy, isotope stratigraphy, geochemostratigraphy, and molecule stratigraphy. Thus, it supplied a perfect base for the establishment of the TAGSSP in the area.

针对研究区二叠系—三叠系界线剖面研究现状，选择了二条陆相剖面，既贵州威宁岔河剖面和哲觉剖面，一条海、陆交互相剖面即云南宣威密德剖面，开展了有关沉积学和层序地层学方面的研究，并结合生物地层、同位素地层、地球化学地层和分子地层等资料探讨了研究区二叠系—三叠系界线的划分与对比方案，从而为在该区争取建立陆相二叠—三叠系辅助层型剖面和点打下了良好基础。

Red birthmark, so long in the face, to the hospital and see the isotope Branch.

是红胎记，好长在面部，到医院的同位素科看吧。

Had proven according to this theory Urey has discovered the hydrogen isotope deuterium existence, however the Bohr theory's further development encounters the insurmountable difficulty, it is unable to process compared to the hydrogen atom slightly for the complex spot helium atom, also inextricability light spectral line intensity question and non-fetter system's question; The Bohr theory also is only the quantal concept and the classical theory mix, theoretically appears is not very harmonious.

根据此理论证明了尤里发现了氢的同位素氘的存在，然而玻尔理论的进一步发展遇到不可克服的困难，它无法处理比氢原子稍为复杂一点的氦原子，也无法解决光谱线的强度问题和非束缚体系的问题；玻尔理论还只是量子概念和经典理论的混合，理论上显得很不和谐。

Taking cave systems under different vegetation in guizhou karst area as study objects, this paper analyzes the spatio-temporal evolution of stable carbon isotope in karst cave system. Vegetation of Liangfeng cave, Qixing cave, Xiniu cave and Jiangjun cave are respectively origin forest, bosk, grassplot and rocky desertification.

本论文在贵州岩溶地区选择了上覆植被分别为原始森林、灌丛草坡、草坡和石漠化的凉风洞、七星洞、犀牛洞、将军洞作为研究对象，对岩溶洞穴系统稳定碳同位素的时空演化规律进行了详细的分析，得出以下几点认识：一。

In addition, the boundary interval is clearly recognizable by the depletion of isotopic carbon ratios and the normal polarity zone appearing above the Late Wuchiapingian reversed polarity zone.

界线层的碳同位素存在明显的负漂移，正磁极性带出现在吴家坪晚期的反极性带之上。

This discovery has provided a good criterion for studying the original carbon and oxygen isotopes of seawater by using the brachiopod shell fossil.

这一发现为利用腕足化石研究海水原始碳氧同位素提供了有力的判据。

For excluding poorly preserved shells, a shell alteration index is suggested to estimate the state of preservation of brachiopod shells through examination under cathodoluminescence and scanning electron microscopes. This study shows brachiopod taxa e.

基于壳体保存程度的详细分析，以阴极发光程度、壳体显微结构为参数建立了壳体成岩作用改造程度的量化模式，经化石壳体氧、碳同位素值的验证，这一模式基本可以用来对不同保存环境下的样品进行筛选。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。