超声萃取—高效液相色谱测定沉积物中的多环芳烃

用正己烷—丙酮(1∶1,体积比)混合液作溶剂,超声萃取提取沉积物中的16种多环芳烃组分.萃取液经硅胶小柱层析净化,旋转蒸发仪浓缩,最后用高效液相色谱—荧光串联紫外检测器分析,并进行加标回收测定.16种多环芳烃的检测限为0.34～1.52 ng· g-1,经精密度试验,相对标准偏差均＜15％,回收率在57.09％～103...     

智能石油产品运动粘度测定仪设计

运动粘度是表征石油产品物理性能的一项重要指标,它表明产品在一定温度下的粘稠情况,单位是平方毫米每秒。介绍了一种以avr单片机为控制核心的智能石油产品运动粘度测定仪,该测定仪具有石油产品运动粘度的测定、显示即时信息、打印报告单、自动清洗等功能。详细的叙述了该石油运动粘度测定仪的原理、硬件组成及软件的设计。     

采用改进Logistic模型预测中国石油消费量

在原有Logistic模型的基础上,增加两个影响模型曲线曲率的参数,得到新的改进Logistic模型.为克服采用常规的优化方法求解模型参数难的问题,采用先进的直接搜索算法——模式搜索法进行模型参数的优化求解,并用Logistic模型和改进的Logistic模型描述中国历年石油消费量数据.结果表明:与原有的Logisti...     

石油焦作还原剂对低品位红土镍矿与赤泥共还原制备镍铁的影响

石油焦作为工业固体废物,其堆积和储存对生态环境产生巨大的影响。本文对石油焦在低品位红土镍矿与赤泥共还原过程中用作还原剂的可行性及其机理进行了研究。通过研究石油焦用量、焙烧温度和焙烧时间等对红土镍矿与赤泥共还原过程的影响,确定最佳的工艺条件为石油焦用量20wt%、焙烧温度1250°C、焙烧时间60 min。在此条件下,可以获得镍品位1.96wt%、铁品位85.76wt%、镍回收率97.83wt%、铁回收率96.81wt%的镍铁产品。扫描电镜和能谱(SEM–EDS)分析结果表明,红土镍矿与赤泥共还原过程中镍和铁主要以镍铁颗粒的形式存在,镍铁颗粒分布均匀且纯度很高,粒径约30 μm。结果表明,石油焦作为还原剂用于红土镍矿和赤泥共还原是可行的,与无烟煤作还原剂相比,石油焦具有成本低的优点。研究结果不仅为石油焦的利用提供了一个新途径,同时也为缺煤地区红土镍矿与赤泥共还原工艺的利用提供了一种解决方案。     

Petroleum-contaminated soil extent recorded by δ15N and δ13C of plants and soils

Petroleum contamination in terrestrial environments caused by industrial activities is a significant problem that has received considerable attention. Carbon and nitrogen isotopic compositions (δ13C and δ15N) effectively describe the behavior of plants and soils under petroleum contamination stress. To better understand plant and soil responses to petroleum-contaminated soil, δ13C and δ15N values of the plants (Trifolium repens, Leguminosae with C₃ photosynthesis pathway, and Agropyron cristatum with C₄ photosynthesis pathway) and the soil samples under one-month exposure to different extents of petroleum contamination were measured. The results showed that petroleum contamination in the soil induced the soil δ15N values to increase and δ13C values to decrease; from 1.9‰ to 3.2‰ and from ?23.6‰ to ?26.8‰, respectively. However, the δ13C values of Agropyron cristatum decreased from ?29.8‰ to ?31.6‰, and the δ13C values of Trifolium repens remained relatively stable from ?12.6‰ to ?13.1‰, indicating that they have different coping strategies under petroleum-contaminated soil conditions. Moreover, the δ15N values of Trifolium repens decreased from 5.6‰ to 0.8‰ near the air δ15N values under petroleum-contaminated soil, which implies that their nitrogen fixation system works to reduce soil petroleum stress. The δ13C and δ15N values of Agropyron cristatum and Trifolium repens reflect changes in the metabolic system when they confront stressful environments. Therefore, stable isotopic compositions are useful proxies for monitoring petroleum-contaminated soil and evaluating the response of plants to petroleum contamination stress.     

我国未来15年石油供需预测与对策

本文在各种建设条件下构建了若干我国石油供需动力模型,在各种假设条件下对我国未来15年的石油供需量进行了数值模拟,并提出了相应的解决我国石油供需矛盾的方案.     

苍耳子提取物的GC/MS分析

本文采用乙醇浸泡提取制得浸膏,再将浸膏加水混悬后依次用石油醚、乙酸乙酯和正丁醇萃取,制得各种提取物。其中石油醚层提取物占总量的50%以上,采用GC/MS对石油醚层进行分析,其主要成分为:亚麻酸乙酯,硬脂酸,正十九烷,亚麻酸甲酯,棕榈酸。     

Multi‐model Forecasts of the West Texas Intermediate Crude Oil Spot Price

We measure the performance of multi‐model inference (MMI) forecasts compared to predictions made from a single model for crude oil prices. We forecast the West Texas Intermediate (WTI) crude oil spot prices using total OECD petroleum inventory levels, surplus production capacity, the Chicago Board Options Exchange Volatility Index and an implementation of a subset autoregression with exogenous variables (SARX). Coefficient and standard error estimates obtained from SARX determined by conditioning on a single ‘best model’ ignore model uncertainty and result in underestimated standard errors and overestimated coefficients. We find that the MMI forecast outperforms a single‐model forecast for both in‐ and out‐of‐sample datasets over a variety of statistical performance measures, and further find that weighting models according to the Bayesian information criterion generally yields superior results both in and out of sample when compared to the Akaike information criterion. Copyright © 2016 John Wiley & Sons, Ltd.     

Micro-terraforming by Antarctic springtails (Hexapoda: Entognatha)

It has long been an axiom of Antarctic terrestrial ecology that interactions between terrestrial invertebrates and their abiotic environment are unidirectional: they are affected by their extreme environment in numerous ways, but they themselves do not affect their environment. Field observations in tandem with laboratory investigations of the exuvial refugia of the springtail Gomphiocephalus hodgsoni Carpenter, reported here, challenge this long-held assumption. These previously undescribed structures consist of minute lithic particulate matter that has been bound together by the accumulation of moult exuviae. Macrophotography, microscopy and manipulation assays demonstrated that the exuviae act as a kind of ‘cement’. Detachment of exuviae by emulsification indicated that this is mediated by the accumulation of cuticular hydrocarbons (retained in shed exuviae) at the lithic–exuvial interface. In addition to re-enforcing preferred microhabitat features by extending the hygrically buffered refuge phenotype, these structures contribute to primary soil formation processes through the structural cohesion of particulate matter. These by-products of moulting behaviour represent the first tangible evidence of environmental modification by terrestrial invertebrates on the Antarctic continent.     

对中外石油合作项目中存在的会计问题的思考

针对我国与西方在石油天然气行业的现行会计制度和行业会计准则在会计处理上存在的很大差异，通过笔者在合作项目中工作的切身体会，分析了石油合作项目中存在的会计问题，并提出了建议。