淖毛湖煤热解重油直接转化制备芳烃化合物研究

采用实沸点蒸馏对新疆淖毛湖煤热解焦油进行了馏分分离,对其中>?320?℃重质馏分进行四组分分析可以发现,胶质含量28.84％,沥青质含量35.12％,属于加氢中很难以转化的组分;13C-NMR结果显示,重油中芳香碳相对摩尔占比71.16％,说明重质馏分中芳香族化合物占主体地位.采用悬浮床+固定床联合裂化工艺处理重质馏分...     

填充毛细管液相色谱-高温毛细管气相色谱在线联用分析润滑油

建立了一套填充毛细管液相色谱－高温毛细管气相色谱在线联用装置,并应用于润滑油的全组分分析。用正相填充毛细管柱液相色谱法进行样品族分离,将润滑油分成烷烃、单环芳烃、双环芳烃、三环芳烃及胶质（多环芳烃和极性物）;特殊设计的多储存位接口可完成一次ＬＣ进样,对样品所有族组成的在线切割、贮存并无损失转入ＧＣ分析,保证了复杂样品全组分分析的准确定性和定量,缩短了分析时间。ＧＣ分析结果给出各族组分的相对含量和碳数分布。     

操作苛刻度对RFCC沉降器内油气重组分的影响

在提升管催化裂化中试装置上,考察了操作苛刻度对重油催化裂化(RFCC)装置沉降器中油气重组分,特别是大于550℃的馏分以及油浆中胶质、沥青质的影响,并结合操作苛刻度对产品分布的影响规律,建立了操作苛刻度函数。结果表明,随着操作苛刻度的提高,油浆中的馏分呈现出中间馏分增加,两端馏分降低的变化趋势,并且油浆中大于550℃馏分的含量明显减少,油浆中的胶质、沥青质含量减少。随着操作苛刻度的提高,在一定范围内轻质油收率基本不变,但是达到一定反应程度后,轻质油产率明显降低。建立的操作苛刻度函数为合理控制操作条件,保证目的产物收率的同时降低了油气中重组分的含量,从而为防止沉降器结焦提供了操作依据。     

渣油加氢反应样品中含铁和含钙化合物溶解性能研究

以某原油及其对应的减压渣油、加氢原料和加氢产品为研究对象,通过柱色谱分离法和溶剂抽提法,对油样中铁和钙化合物在组分中的含量、分布以及存在形态进行了研究。研究结果表明,柱色谱分离过程中,油样中的含铁或钙的化合物在色谱柱上产生吸附,损失了58%的铁化合物和76%的钙化合物;溶剂抽提法能够有效减少组分中金属元素的损失。原油中97%以上的铁和钙分布在减压渣油馏分中,减压渣油中60%-90%的铁和钙分布在胶质、沥青质组分中。渣油加氢反应过程中,铁、钙化合物主要是从胶质中得到脱除,整体脱除率接近30%,铁化合物更易结合在沥青质中而难以脱除。原油经过常减压蒸馏后,油溶性铁相对分布由95.6%降低为64.7%,水溶性铁相对分布由4.4%升高为35.3%。经过加氢反应后,38%左右的油溶性铁在反应中转化为水溶性铁,30%左右的油溶性钙在反应中转化为水溶性钙。     

气提吸附／热脱附／气相色谱－质谱法分析污水中的痕量有机物

 采用气提吸附／热脱附／气相色谱－质谱法对齐鲁公司所处地区工业污水进行分析。方法采用Ｔｅｎａｘ－ＧＣ吸附剂对样品进行气提吸附，脱附时样品直接进入色谱仪汽化室，一次进样即可完成全组分分析，共检测出含四氯丙醚在内的４０种有机组分，测定了各组分的程序升温保留指数。气相色谱－质谱法测定出四氯丙醚三个异构体的结构。     

气提吸附／热脱附／气相色谱－质谱法分析污水中的痕量有机物

采用气提吸附／热脱附／气相色谱－质谱法对齐鲁公司所处地区工业污水进行分析。方法采用Ｔｅｎａｘ－ＧＣ吸附剂对样品进行气提吸附，脱附时样品直接进入色谱仪汽化室，一次进样即可完成全组分分析，共检测出含四氯丙醚在内的４０种有机组分，测定了各组分的程序升温保留指数。气相色谱－质谱法测定出四氯丙醚三个异构体的结构。     

稀土改质催化剂对废食用油制备燃料油的影响

利用浸渍法制备稀土改质催化剂,用于废食用油脂催化裂解的裂解气催化改质。考察了催化剂活性组分含量、硅铝比、焙烧温度、改质反应温度对产物组成、烯烃含量及收率的影响。得最佳条件:ZSM-5作为催化剂载体,催化剂活性组分镧稀土含量为6%,催化剂焙烧温度为550℃,改质反应温度为360℃。在最佳条件下催化改质,燃料油烯烃含量降低了34.3%,汽油含量提高了14.36%,轻柴油含量提高了1.67%,重柴油含量下降了6.72%,重油含量下降了2.2%,燃料油总收率提高了7.12%,油品质显著提高。     

Pingba RP-3喷气燃料中有色组分的鉴定及其特性研究

用中性氧化铝吸附、无水乙酸脱附的方法，对储存中变色的Pingba RP-3喷气燃料中的有色组分进行分离制备。应用有机元素分析、红外光谱、色质联用和裂解色质联用等分析法对富集有色组分的吸附胶质进行了分析鉴定，对燃料的储存特性和有色组分的化学特性进行了考察。结果表明，Pingba RP-3喷气燃料中的有色组分全部集中在吸附胶质中，吸附胶质以含氧化合物为主，其主要成分为烷基苯酚类（及其多聚体）化合物，含氮化合物质量分数极少，未检出含硫化合物。Pingba RP-3在储存中颜色变深的主要原因是胶质中的烷基苯酚类化合物氧化和缩聚。储存过程中喷气燃料的吸附胶质和颜色增加显著，与燃料在一定条件下的氧化反应有关。     

金属助剂对Pt/SAPO-11催化剂物化及异构性能的影响

通过浸渍法制备了Pt/SAPO-11催化剂,分步浸渍法制备了LaPt/SAPO-11、CePt/SAPO-11和SnPt/SAPO-11双金属催化剂。通过X射线衍射、低温氮物理吸附、氨程序升温脱附、氢气化学吸附和吡啶吸附红外等手段对所得样品进行了表征。实验结果表明,助剂的引入导致了催化剂的比表面积和微孔孔容降低,B酸量减少而L酸量增加,总酸量有所下降,Pt组分的分散度提高。在360℃时,对正庚烷的临氢异构化反应中,Pt/SAPO-11催化剂的正庚烷转化率为65.14%,C7异构体收率为61.67%;当分别加入La和Ce,Pt/SAPO-11的正庚烷转化率提高至77.40%和78.12%,C7异构体收率分别提高至69.72%和68.48%;而加入Sn后,Pt/SAPO-11的正庚烷转化率和C7异构体收率分别降至63.22%和59.09%。     

毛细管液相色谱高温毛细管气相色谱在线联用方法在原油族组成分析中的应用

 原油经过脱沥青处理后 ,采用填充毛细管液相色谱 (PC HPLC)与高温毛细管气相色谱 (HTGC)在线联用技术分析原油中的脂肪烃、芳烃、胶质。样品经过PC HPLC族分离后 ,各族组分峰被依次切割并存放在多位储存接口内 ,再分别无损失地转入GC进行各族组分的定量分析。方法简单、灵活 ,重复性误差 (RSD)≤ 3%。     

On-line fermentation gas analysis: Error analysis and application of mass spectrometry

On-line fermentation gas analysis is of general interest because it permits the determination of metabolic rates in almost any biological process using living organisms. The consumption and production of gases (O₂, CO₂, CH₄, etc.) and volatile compounds may be determined without causing any risk of infection. Elemental balancing permits the determination of other metabolic rates if the stoichiometry is known. This was studied with the production of poly-β-hydroxybutyrate (PHB) by Alcaligenes latus. Estimations were based on the measurement of gas partial pressure and flow-rates, pH and alkali consumption rate. Experiments with a small quadrupole mass spectrometer showed unacceptable error propagation. Therefore, dynamic error propagation for all rates was studied using simulation. It was found that, for example, a 1% relative offset-calibration error for oxygen can result in an error in PHB estimation of > 50%. It is suggested that this culture is used in combination with elemental balancing for thorough tests of the accuracy of on-line gas analysis equipment. An on-line process gas analyser based on a quadrupole mass spectrometer (Balzers PGM 407) gave the following precision values (abs. vol.?%) during cultivation of Bacillus subtilis: nitrogen (m/z 14), 0.024; oxygen (m/z 32), 0.020; argon (m/z 40), 0.0011; and carbon dioxide (m/z 44), 0.0034. These values, combined with automatic recalibration, would be sufficient for reasonable estimation of PHB, biomass and substrates.     

Impact of alkali treatment on physico-chemical,thermal, structural and tensile properties of Carica papaya bark fibers

This study aims to examine the effect of sodium hydroxide (NaOH) treatment on the physico-chemical properties, structure, thermal, tensile and surface topography of Carica papaya fibers (CPFs). The surface of raw CPFs was modified by soaking with 5% NaOH solution for 15, 30, 45, 60, 75 and 90?min. The results of thermo-gravimetric analysis revealed that the optimum treatment time for alkali treatment was 60?min. It was found that the alkali treatment improved the properties of the CPFs. The results of TGA, FT-IR, XRD and AFM suggest that the treated CPF is a suitable alternative as reinforcement in polymer composites.     

Chemometric and trend analysis of water quality of the South Chennai lakes: an integrated environmental study

In order to bring out the nature of the factors influencing lake water composition, multivariate statistical analysis and trend analysis were performed based on the hydrochemical data of the study area, namely, South Chennai. Change in land use pattern and settlements along the banks of the lakes alters the quality and quantity of the surface water. In the present study, the R‐mode factor analysis and cluster analysis were applied to the geochemical parameters of the water to identify the factors affecting the chemical composition of the lake water. Dendograms of both the seasons give three major clusters, reflecting the groups of unpolluted to moderately polluted, polluted, and heavily polluted stations. The movement of stations from one cluster to another clearly brings out the seasonal variation in the chemical composition of the lake water. The complex hydrochemical data of the surface water were interpreted by condensing them into three major factors. Factor score analysis was used successfully to delineate the stations under study and the role of the contributing factors, and the nature of factors responsible for the variation in chemical composition of the water has been clearly brought out. Results of trend analysis using ArcGIS clearly indicate that the trend in water quality is deteriorating at a faster rate in the eastern part of the study area. It is understood that although natural shifts probably can account for some of the variation, it is most likely that human activities play a major role in affecting the water quality on a regional scale. Copyright © 2014 John Wiley & Sons, Ltd.     

Time-series analysis in analytical process control

Analysis of time series tries to extract tendencies from measured values dependent on time. For this purpose the cusum technique has proved to be a very sensitive tool for the evaluation of both current and completed time series. Even very weak tendencies can be detected at a high level of noise. Time-series analysis further tries to predict values to come from hitherto performed measurements. As a very flexible model exponential smoothing could be successfully used. Even for processes with a high extent of non-stationarity this model allowed a good prediction owing to the dynamics of the process. Three types of time-series analysis, i.e., evaluation of current measurements, retrospective evaluation and prediction of data (also known as “in vivo”, “post mortem” and “in futurum” time-series analysis) are demonstrated for problems stemming from analytical process control.     

Determination of rank by augmentation (DRAUG)

Determining the rank of a chemical matrix is the first step in many multivariate, chemometric studies. Rank is defined as the minimum number of linearly independent factors after deletion of factors that contribute to random, nonlinear, uncorrelated errors. Adding a matrix of rank 1 to a data matrix not only increases the rank by one unit but also perturbs the primary factor axes, having little effect on the secondary axes associated with the random errors in the measurements. The primary rank of a data matrix can be determined by comparing the residual variances obtained from principal component analysis (PCA) of the original data matrix to those obtained from an augmented matrix. The ratio of the residual variances between adjacent factor levels represents a Fisher ratio that can be used to distinguish the primary factors (chemical as well as instrumental factors) from the secondary factors (experimental errors). The results gleaned from model studies as well as those from experimental studies are used to illustrate the efficacy of the proposed methodology. The method is independent of the nature of the error distribution. Limitations and precautions are discussed. An algorithm, written in MATLAB format, is included. Copyright © 2011 John Wiley & Sons, Ltd.     

新材料的发展与分析化学

文章介绍了新材料的重要性及发展方向,分析化学在新材料研制中起着耳目的作用,另一方面新材料也为分析化学的进展提供了课题与条件。微量分析、微区分析、表面分析是此领域中的重点。在未来的发展中,分析化学在材料的发展中的地位不会改变,并期待着分析灵敏度与空间分辩率的进一步提高。     

Automatic window factor analysis—A more efficient method for determining concentration profiles from evolutionary spectra

An algorithm called automatic window factor analysis (AUTOWFA) is developed for the purpose of determining, efficiently and automatically, the concentration profiles of the spectroscopically active components present in evolutionary processes, such as chemical titration, chromatography and kinetics. The method not only yields windows and profiles in agreement with those reported in the literature, but also reveals components not detected by precursor techniques. The method, however, has not been optimized and may require user interaction to fine-tune the windows.     

Determination of Mercury in Geological Materials by Continuous-Flow,Cold-Vapor,Atomic Absorption Spectrophotometry

Abstract

To determine mercury in geological materials, samples are digested with nitric acid and sodium dichromate in a closed teflon vessel. After bringing to a constant weight, the digest is mixed with air and a sodium chloride-hydroxylamine hydrochloride-sulfuric acid solution and then Hg(II) is reduced to Hg with stannous chloride in a continuous flow manifold. The mercury vapor is then separated and measured using cold vapor atomic absorption spectrophotometry (CV-AAS). For a 100 mg sample the limit of detection is 20 parts per billion (ppb) Hg in sample. To obtain a 1% absorption signal, the described method requires 0.21 ppb Hg solution (equal to 16 ppb in sample). Precision is acceptable at less than 1.2% RSD for a 10 ppb Hg aqueous standard. Accuracy is demonstrated by the results of the analysis of standard reference materials. Several elements do interfere but the effect is minimal because either the digestion procedure does not dissolve them (e.g., Au or Pt) or the; are normally of low abundance (e.g., Se or Te).