查询词典 alkanes

The carbon isotope composition of single alkanes (δ13Cia) in two plants (Leontopodium leontopodioidies and Taraxacum mongolicum ) growing in the northeastern Qinghai-Tibet plateau was analyzed by means of GC-IMS in order to know its relationship with altitude,and furthemore, to gain new data for the research on climatic changes.

用色谱—同位素质谱仪对青藏高原东北部高寒草甸生态系统中的两种高等植物—火绒草和蒲公英的烷烃进行分析，讨论环境因素对植物单体烷烃碳同位素组成（δ13Cia）的影响。

Result The results showed that its components were quite complex, and 89 organic compounds were identified. There were 72 kinds of oxygen-containing organic compounds which included esters, phenols, aethers, ketones and alcohols in the depolymerization product, small amounts of alkanes, alkenes, arenes, thiophenol and nitrogen-containing organic compounds were also detected, which showed that characteristics of the product with high oxygen content, low nitrogen and sulphur content.

结果］超临界乙醇解聚产物成分十分复杂，GC/MS分析鉴定出89种有机化合物，其中72种为含氧化合物，主要有酯、酚、醚、酮和醇等，还检测出少量烷烃、烯烃、芳烃、苯硫酚和含氮化合物，反映了解聚产物的高含氧量和低含氮硫量的特性。

The preliminary tracing study on pollutant source using some molecular geochemical parameters was conducted. The results indicate that the smaller sizes of airborne particle result in the lower CPI value and a stronger tendency of unimodal distribution for n - alkanes.

运用分子地球化学参数对污染源进行的初步示踪研究结果表明，颗粒物粒径越细，正构烷烃越趋向于单峰形分布，碳优势指数越低。

All the compounds were isolated and identified from the bituminous coals for the first time, bis(2-ethylheptyl) terephthalate and 18-ethyl-17-(hexan-2\'-yl) docosanoic acid are new compounds.Further more, a Colourless Oil Liquid, a white acerate crystals containing some alkanes, a white tabular crystals consisting of some fatty acid esters and a white powder crystals in which some fatty acids exist were isolated and analysed by GC/MS for the first time.Through this research, a study method of"classification extract of bituminous coal- separation with silica-gel and gelatin column chromatographies- identification of the isolated compounds by FTIR, GC/MS, LC/MS, 1H NMR and 13C NMR analyses"was established and proved to be a practical approach toward separable and non-destructive identification of some organic compounds in bituminous coals for coal chemistry research.

本研究建立了&原煤分级萃取-硅胶与凝胶柱层析分离与纯化-GC/MS或LC/MS检测-FTIR、MS、1H NMR和13C NMR波谱解析&这一煤中有机化学成分的非破坏性分离与分析的研究方法，并验证该研究方法有效可行。

Then the molecular structure information connectivity indices of 22 alkoxyl silicon chlorides , 61 sulfides and 74 alkanes were calculated.

利用线性回归技术分别建立了 22个烷氧氯硅烷、61个单硫醚化合物的mY与这些物质的气相色谱保留指数RI的定量结构/保留相关关系模型。

Previous studies have showed that bicyclic alkanes and MMAs biomarkers in sediment are related to the parent material import of Botryococcus braunii.

前人研究表明，葡萄藻可能是地质体中两环倍半萜和单甲基支链烷烃的重要母质来源。

The results show that the formation of dry gas is abided by reaction mechanism involving the cleavage of pentacoordinated Carbonium ion which is formed by the protonation of alkanes over acidic catalyst.

结果表明，烷烃分子首先在催化剂酸性中心作用下发生质子化反应，烷烃分子链上易受到氢质子进攻的位置一般在其叔碳原子或碳链中心碳原子附近的C—H键或C—C键处，形成两种反应过渡态物种——五配位正碳离子H-Carbonium和C-Carbonium。

The elaboration of systems that are able to mimic those enzymes should provide very important tools for three main purposes:(1) the development of new catalysts for important reactions in industrial and fine chemistry, such as the selective oxidation of alkanes and the stereoselective epoxidation of alkenes;(2) the prediction of the oxidative metabolism of new biologically active molecules such as drugs.(3) mimetic peroxidase of high catalytical activity and selectively is very important in bio-analytical field.

建立一系列关于这些酶的模拟体系将为以下三个方面的研究工作提供非常重要的工具：（1）工业或者精细化工方面重要反应新型催化剂的开发，例如烷烃的选择性氧化以及具有立体选择性的烯烃环氧化；（2）新的生物活性物质，例如药物的氧化机理的研究和预测；（3）具有合适底物的高活性过氧化物酶模拟酶在生化分析领域的前景。

The biomarkers such as the n-Alkanes, the isoprenoids, the terpane, and cholestane were detected through GC-MS analysis. Based on the study of the biomarkers, the biological evolution during Permian and Triassic can be divided as three stages, namely, the mixing source stage of low biota such as thallose and advanced plant in late Permian (below bed 63), the stage of low biota such as thallose in the boundary transitional layer (bed 63-69) and the mixing source stage of advanced plant and low biota such as thallose in early Triassic (above bed 69). What's more, the second stage near the boundary transitional layer can be subdivided into 4 stages. The stages of biota evolution is close related with sedimentary environment changing and the boundary transitional layer.

利用GC—MS分析技术，在陆相地层中检测出正构烷烃、类异戊二烯烷烃、萜烷和甾烷类生物标志化合物并根据生物标志化合物和特征值研究，将二叠系—三叠系生物演化划分为三个大的阶段，即晚二叠世的菌藻类低等生物与高等植物混源阶段（63层以下），界线异常层的菌藻类低等生物阶段（63-69层）和早三叠世高等植物与菌藻类低等生物混源阶段（69层以上），界线附近异常层的第二阶段又进一步细分为4个次一级阶段，生物演化阶段与沉积环境变化及界线异常层具有非常密切关系。

The main conclusions of this thesis were as follows: 1 Through compared the original peaks, relative concentration distribution and diagnostic ratios of normal alkanes,Naphthalene, Dibenzothiophene, Fluorene, Phenanthrene, Chrysene and their alkyl PAHs, terpane-sterane biomakers of five crude oils, it was confirmed that five single crude oil was unmatched each other.

通过正构烷烃、萘、菲、芴、二苯并噻吩、屈及其烷基化系列多环芳烃、甾萜类生物标志物的原始谱图比较；组分浓度的分布模式比较；诊断比值的比较；对5种不同地质层次的原油进行了鉴别，结果表明5种原油均为独立油样，这与实际情况相符和；t检验分析的使用，使得溢油鉴别更加科学化，定量化；SPSS模糊聚类的使用，使得各油样之间&亲疏远近&的关系，即&属于的程度不同&的概念得以充分表现；明确了&是非&分明的概念。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。