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In view of the changes which have taken place in this field in recent years, it is perhaps a suitable time to review the fundamentals of the subject, in order that the significance of recent developments might not be lost for the surface coatings analyst.

In view of the current difficulty of separation of troxerutin, the purpose of the paper is to separate and purify semi-synthetic flavonoid compound troxerutin by macroporous adsorption resin (SZ-3).

Comparing the adsorption performance and resolution of three different polar resins and choosing a resin to optimize the process parameters such as sample volume, eluent concentration and elution temperature to obtain high-purity troxerutin. After separating and enriching by resin column chromatography, detected the sample by LC-MS analysis.

This research found that the optimal conditions of the adsorption and desorption were sample volume S = 90 mg/g resin, methanol concentration C = 25%, T = 20 °C. the content of troxerutin increased significantly from 88% to more than 96%. Then confirmed the sample was troxerutin by LC-MS. In addition, the resin could be used for at least 10 cycles in the separation and purification experiments of troxerutin.

Purification of troxerutin with new SZ-3 resin for the first time. Under the optimal conditions, the purity and recovery of troxerutin was 96.4% and 39%. In this study, the authors established a purification process of troxerutin successfully that was simple, economical, environment friendly, with high purity and high recovery rate to provide a reference program for changing the status of troxerutin separation difficulties.

The increase in seafood trade in recent years motivates more detailed studies of different species, as well as evaluation of the nutritional quality of their lipid content. Thus, the purpose of this paper is to evaluate the fatty acid composition, especially the concentrations and fractionation of omega‐3 essential fatty acid in classes of mussels (male and female), oysters, squid, and octopus captured on the south coast of Brazil.

Fatty acid methyl esters were prepared by methylation of total lipids and were separated by gas chromatography. Quantification of LNA, AA, EPA, and DHA was done against tricosanoic acid methyl ester as an internal standard. Total lipids were fractionated into neutral lipids and polar lipids by classical column chromatography.

The results of this study were as follows: the female mussel had the highest lipid content (3.52 per cent), followed by the male mussel (2.70 per cent), squid (1.05 per cent), octopus (0.79 per cent), and oyster (0.62 per cent). The samples that had the highest percentages of EPA and DHA in their lipid fraction were the female mussel and squid, respectively. The species belonging to the Bivalvia class (mussels and oysters) showed a predominance of PL, while those belonging to the cephalopods class (octopus and squid), showed a predominance of NL. The n‐6/n‐3 and polyunsaturated fatty acid/saturated fatty acids ratios of all samples analyzed were in accordance with the recommendations. The female mussel had the highest concentration of EPA+DHA omega‐3 fatty acids, corresponding to 1,064.63 mg EPA+DHA 100 g⁻¹ of the sample. So, the consumption of mussels caught off the southern coast of Brazil provides the omega‐3 essential fatty acids.

This paper provides important data concerning lipid quality of seafood caught off on the south coast of Brazil.

Because of the increasing global oil demand, efforts have been made to further extract oil using chemical enhanced oil recovery (CEOR) methods. However, unlike water flooding, understanding the physicochemical properties of crude oil and its sandstone reservoir makeup is the first step before embarking to CEOR projects. These properties play major roles in the area of EOR technologies and are important for the development of reliable chemical flooding agents; also, they are key parameters used to evaluate the economic and technical feasibilities of production and refining processes in the oil industries. Consequently, this paper aims to investigate various important physicochemical properties of crude oil (specific gravity; American Petroleum Institute [API]; viscosity; pour point; basic sediment and water; wax; and saturate, aromatic, resins and asphaltenes components) and sandstone reservoir makeup (porosity, permeability, bulk volume and density, grain volume and density, morphology and mineral composition and distributions) obtained from Malaysian oil field (MOF) for oil recovery prediction and design of promising chemical flooding agents.

Three reservoir sandstones from different depths (CORE 1; 5601, CORE 2; 6173 and CORE 3; 6182 ft) as well as its crude oil were obtained from the MOF, and various characterization instruments, such as high temperature gas chromatography and column chromatography for crude’s fractions identification; GC-simulated distillation for boiling point distribution; POROPERM for porosity and permeability; CT-Scan and scanning electron microscopy-energy dispersive X-ray for morphology and mineral distribution; wax instrument (wax content); pour point analyser (pour point); and visco-rheometre (viscosity), were used for the characterizations.

Experimental data gathered from this study show that the field contains low viscous (0.0018-0.014 Pa.s) sweet and light-typed crude because of low sulfur content (0.03 per cent), API gravity (43.1o), high proportion of volatile components (51.78 per cent) and insignificant traces of heavy components (0.02 per cent). Similarly, the rock permeability trend with depth was found in the order of CORE 1 < CORE 2 < CORE 3, and other parameters such as pore volume (Vp), bulk volume (Vb) and grain volume (Vg) also decrease in general. For grain density, the variation is small and insignificant, but for bulk density, CORE 2 records lower than CORE 3 by more than 1 per cent. In the mineral composition analysis, the CORE 2 contains the highest identified mineral content, with the exception of quarts where it was higher in the CORE 3. Thus, a good flow crude characteristic, permeability trend and the net mineral concentrations identified in this reservoir would not affect the economic viability of the CEOR method and predicts the validation of the MOF as a potential field that could respond to CEOR method successfully.

This paper is the first of its kind to combine the two important oil field properties to scientifically predict the evaluation of an oil field (MOF) as a step forward toward development of novel chemical flooding agents for application in EOR. Hence, information obtained from this paper would help in the development of reliable chemical flooding agents and designing of EOR methods.

As the concentration of environmental samples was generally very low and existing analytical instruments had limited sensitivity, developing mini pre-treatment systems for effectively concentrating the components was very important and necessary. The purposed of this paper is to develop mini pretreatment system integrated with micro pre-concentrator and micro GC column.

In this work, a mini pre-treatment system integrated with a micro pre-concentrator and a micro gas chromatograph (GC) column was proposed. The micro pre-concentrator filled with single-walled carbon nanotubes as adsorbent materials was able to effectively concentrate the trace environmental sample, which dramatically improved the response of detectors. In addition, instead of conventional columns, micro GC columns were able to effectively separate gas mixtures, which are able to overcome low resolution and poor anti-interference ability of portable instruments.

The results demonstrated that the proposed pre-treatment system was able to concentrate the trace sample with a concentration factor of 15 and effectively separate the gas mixtures with a resolution over 1.5.

A mini pre-treatment system integrated with a micro pre-concentrator and a micro GC column was proposed.

For the separation and isolation of simple chemical compounds, the molecular weights of which in general do not exceed 600, gas chromatography offers one of the most flexible and adaptable analytical techniques available in the modern laboratory. It is only just over 25 years ago that the first successful applications of this technique were reported by James and Martin, yet modern commercial gas chromatographs exhibit a high degree of refined engineering applied to the separation procedures themselves which, when combined with microprocessor control and other recent developments in the field of electronic data handling, offer to the analyst considerable scope for the examination of even the most intractable samples. In the paint industry the facilities offered by gas chromatography are being fully exploited in the analysis of raw materials, notably solvents, monomers, oils and fats; in the analysis of finished paints and in the control of the working environment as demanded by present‐day health and safety regulations. This article presents a review of the analytical procedures that are possible using modern gas chromatography techniques.

Until comparatively recently, in the practice of gel permeation chromatography it has been customary to use porous gel beads that have an average diameter in the range between 75 and 100 microns, and which are packed into columns up to 4ft long and having an inside diameter of approximately 0.3in, in order to achieve a separation. A working pressure in the region of 40 psi is normal for each of these columns when eluted with solvents such as toluene or tetrahydrofuran (THF) at ambient temperature. Therefore, a pump that is capable of producing a steady pulseless flow at around 300 psi is sufficient to meet the working requirements of a combination of up to seven such GPC columns. At the customary flow rate of 1cm3 min‐1 a chromatograph equipped as described would produce a GPC scan of whole polymer in about 3 hours.

Until recently liquid chromatography has been a somewhat neglected branch of science. However, the availability of precision equipment, and even complete instruments, has made possible liquid chromatography separations of a more advanced nature. For example, suitable detectors have been developed, and pumps are available which deliver accurate volumes of solvent under pressure.