查询词典 trace elements

With the development of science and technology, sensitive, rapid, reproducible, simple and accurate analytical methods are required for the determination of trace elements in geological, biological and environmental samples. The direct determination of extremely low concentration of trace element with modern atomic spectroscopic method, such as atomic absorption spectrometry is so difficult. On one hand, the limitations are associated not only with the insufficient sensitivity of these techniques but also with matrix interference.

随着科学技术技术的发展，在进行地质、环境、生物等样品中痕量金属元素的测定时，常常要求达到ppb级的水平，虽然火焰原子吸收分光光度法具有很高的灵敏度，但是要直接测定这些样品中的痕量组分却很难，这是因为，一方面，样品本身的物理化学状态有的不适合直接测定，或组分的含量低于分析方法的灵敏度；另一方面是存在基体干扰。

All the volcanic rocks present younger K-Ar age (less than 5Ma), which can be termed as Cenozoic rocks. In general speaking, volcansim can be dividied into two eruptive stages. In the first stage, volcanic rocks for Pliocene epoch (4. 4-5Ma) consist of basanite and tephrite, which distributed on Mt. Crater, Cape Bird, and southern bank of Bonney Lake; In the second stage, volcanic rocks for Quaternary (less than 1 Ma) are mainly composed of latite, which are distributed on Cape Rodeys and Cape Evens.On the basis of geochemical data such as major elements, trace elements , rare earth elements, isotope, microprobe analysis, combined with main achievement taken by previous researcher in this area, conclusions are drawn basically as follows

所喷发的火山岩K-Ar年龄值均小于5Ma，为新生代火山岩，大体上可以分为两个喷发阶段，第一个阶段为上新世火山岩(年龄值为4.4-5.0Ma)，主要由碧玄岩和碱玄岩组成，分布于罗斯岛上的克雷克特山、鸟角和泰勒谷的博尼湖南岸；第二阶段为第四纪火山岩(年龄值均小于1Ma)，主要由安粗岩组成，分布于罗斯岛上的罗德角和伊万思角，通过主要元素、微量元素、同位素结合电子探针以及前人的研究成果，我们大体上可以得出如下认识

The geochemical characteristics and depositional environment of Pengcuolin chert are studied based on the field investigations and analysis on major elements, trace elements and rare earth elements.

通过野外地质调查和系统的岩石化学、常量元素、微量元素以及稀土元素等研究，探讨了藏南彭错林硅质岩的地球化学特征及其沉积环境。

To determinate the inorganic elements levels in Semen Cassiae,and to study on the pharmacologic substance basis and the influence parching processing on the content of elements of it,trace elements and heavy metals in Semen Cassiae and its preparation Cultivated in different areas were determined by atomic fluorescence spectrometry and inductive coupled plasm a atom emission spectrometry.

为测定生决明子中无机元素水平，探讨其药效物质基础及炒制对其含量的影响，采用原子荧光法和等离子发射光谱法等测定了不同产地、批次的生、炒决明子中重金属及微量元素的含量。

ResultsThe leaves of Capparis spinosa contained 13 species of elements, including 4 species of microelements, 6 species of trace elements and 3 species of weight elements. Except for Cd, the contents of heavy metal Pb and Cr were much lower than the national standards of food hygiene.

结果刺山柑叶子富含K，Ca，Mg，Na 4种常量元素和Fe，Zn，Mn，Cu，Ni，Co 6种微量元素，重金属元素Pb，Cr的含量均低于国家标准。

Some essential trace elements were reported to be involved in the normal bone metabolism. Nowadays rare earth elements are widely used in many fields and more and more rare earth elements enter the environment and food chains They are enriched in bone and difficult to be excreted. Because the similarity between rare earth ions (Ln3+) and Ca2+, they will intervene and regulate bone formation and remodeling.

骨骼的正常代谢涉及多种金属离子，随着稀土的应用，通过环境和经由食物链等渠道进入人体内的稀土量也有所增加，并且在骨组织中相对富集且难排出；由于稀土与钙离子的相似性，它们将干预和调控骨的形成与再造。

Some essential trace elements were reported to be involved in the normal bone metabolism. Nowadays rare earth elements are widely used in many fields and more and more rare earth elements enter the environment and food chains. They are enriched in bone and difficult to be excreted. Because the similarity between rare earth ions Ln(superscript 3+ and Ca(superscript 2+), they will intervene and regulate bone formation and remodeling.

骨骼的正常代谢涉及多种金属离子，随着稀土的应用，通过环境和经由食物链等渠道进入人体内的稀土量也有所增加，并且在骨组织中相对富集且难排出；由于稀土与钙离子的相似性，它们将干预和调控骨的形成与再造。

According to the strata about the trace elements in coal of China ,the different background value of trace elements in different parts of China were d rew out.

由于分析样品分布不均和采用的测试方法各不相同，本文的数据还不能准确地代表中国煤中微量元素的平均丰度值。

It is well known that Huang-huai-hai Plain flourished around Han and Tang dynasties, not only boasted of the highly developed agricultural economy, handicraft industry and cultural education, but also of the population quality and proportion. while the physiognomy of the Plain has changed greatly since Song and Yuan dynasties due to the frequent deluge and the river course change of Yellow River, which caused the changes of the trace elements amount in the plain\'s soil, especially the decrease of virtual zinc which caused the cultural developing process to stagnate gradually after Song and Yuan dynasties. Trace elements like a invisible hand worked uniquely on cultural developing process.3The geographical environment and the morbid population of Lin Xiang Kingdom in Sun-Wu Kingdom Period.

二地理环境下的土壤微量元素的变化状况与历史时期黄淮海平原文明进程的关系：众所周知，汉唐时期是黄淮海平原地区文明程度最高的时期，不仅农业经济、手工业经济和文化教育高度发展，而且人口素质和人口比重也是占据极为重要地位；但是，由于黄河的频繁泛滥和改道，不仅造成了黄淮海平原地貌的巨大变化，而且也引发了黄淮海平原土壤微量元素的变化，以致有效锌严重缺乏，从而使得宋元以后的黄淮海平原的文明进程逐渐停滞下来；而在此过程中，土壤微量元素锌像一支看不见的手在起着独特的作用。

A series or criteria of recognizing tin-bearing granite is set up by collecting the data on related petrology, mineralogy, geochemistry, trace elements, transitional ele ments, incompatible elements and rare earth elements.

黑云母花岗岩对成矿的贡献有两个突出的方面：其一是其在重熔生成演化过程中，经高度分异作用，将原各地质体中的锡多金属元素分馏富集，为成矿奠定了一个良好的基础。

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。