Simultaneous Experimental Analysis of Oil Content And Molecular Composition of Shale Fractions

The important research content and basis of exploration and development is to evaluate the reservoir property, oil bearing property, fluidity and compressibility of shale reservoir.The key of exploration and development is to evaluate the oil-bearing and fluidity of shale reservoir.In this paper, the "shale oil content and fine components synchronous experimental analysis device" is used. Five temperature ranges of 30 ℃-90 ℃, 90 ℃-150 ℃, 100 ℃- 200 ℃, 150 ℃-250 ℃ and 250 ℃-300 ℃ were adopted. The heating rate of each temperature segment was 25 ℃ / min, and the final temperature was kept constant for 5 min. The oil content of shale (pyrolysis S1) was cut into five fractions.Simultaneous determination of oil content and molecular composition of shale fractions,and the external standard method was used to evaluate the oil content and fluidity.The results show that the five fractions of shale are mainly composed of nC1-nC9 gas, nC10-nC15 gasoline, nC12-nC20 kerosene, nC15-nC22 diesel oil and nC18-nC26 heavy oil of the first member of Qingshangkou formation in Songliao basin.There are differences in the fractionation and oil content characteristics of samples with different maturity in different wells.The parent material, properties and quality of crude oil are reflected in shale. The higher the maturity of shale oil is, the more light components are, the larger the light / heavy ratio parameter value of (gasoline + kerosene + diesel) and heavy oil is, the better the fluidity is, and the easier to exploit effectively.

Simultaneous Determination of Four Ingredients in Plantago Depressa by Single Marker

Objective. To establish a quantitative analysis of multicomponents by single marker (QAMS) method for the simultaneous determination of 4 active components such as protocatechuic acid, catechin, quercetin, and luteolin in Plantago depressa. Method. 4 active components in Plantago depressa were studied. Quercetin was used as an internal reference to establish the relative correction factors among protocatechuic acid, catechin, and luteolin and calculate the contents of each component; the results were compared with those measured by the external standard method. Results. 4 components showed a good linear relationship in their respective concentration ranges (r > 0.9995). The relative correction factors (fs/k) of protocatechuic acid, catechin, and luteolin were 1.1992, 0.8613, and 1.6069, respectively. The method had good durability. The contents of protocatechuic acid, catechin, and luteolin calculated by QAMS were not significantly different from those measured by the external standard method. Conclusion. QAMS can be used to determine the content of 4 components in Plantago depressa at the same time, and the method is simple, accurate, and can be used for quality control.

Rapid Simultaneous Determination of 43 Pesticide Residues in Schizonepeta tenuifolia by Gas Chromatography Mass Spectrometry

A simple, fast, and reliable method was established for simultaneous determination of 43 pesticides in Schizonepeta tenuifolia. The samples were prepared using solid-phase extraction (SPE) method. Pesticides were extracted from Schizonepeta tenuifolia using acetonitrile, cleaned with Pesticarb/NH2, and eluted by mixed solvents of acetonitrile and toluene (3 : 1, v/v). Selected pesticides were identified using DB-35MS capillary column and detected by gas chromatography mass spectrometry. Samples were quantified by external standard method. Recoveries for the majority of pesticides at spike levels of 0.2, 0.5, and 1 mg kg−1 ranged between 70 and 120% (except for Chlorothalonil, Thiamethoxam, and Dicofol), and the relative standard deviations (RSDs n = 6) were 1.32%–13.91%. Limits of detection (LODs) were 0.0011–0.0135 mg kg−1, whereas limits of quantification (LOQs) were 0.0038–0.0451 mg kg−1. The satisfactory accuracy and precision, in combination with a good separation and few interferences, have demonstrated the strong potential of this technique for its application in Schizonepeta tenuifolia analysis.

Simultaneous Determination of 23 Mycotoxins in Broiler Tissues by Solid Phase Extraction UHPLC-Q/Orbitrap High Resolution Mass Spectrometry

Mycotoxins are a type of toxins harmful for not only animal but also human health. Cooccurrence of multi-mycotoxins could occur for food infected by several molds, producing multi-mycotoxins. It is necessary to develop corresponding determination methods, among which current mass spectrometry (MS) dominates. Currently, the accurate identification and quantitation of mycotoxins in complex matrices by MS with low resolution is still a challenge since false-positive results are typically obtained. Here, a method for the simultaneous determination of 23 mycotoxins in broiler tissues using ultra-high performance liquid chromatography-quadrupole/orbitrap HRMS was established. After the extraction by acetonitrile-water-formic acid (80:18:2, v/v/v), the purification by multifunctional purification solid phase extraction cartridges and the chromatographic separation on a C18 column, representative mycotoxins were determined by HRMS in full scan/data-dependent MS/MS acquisition mode. The quantitation was based on the external standard method. An MS/MS database of 23 mycotoxins was established to achieve qualitative screening and simultaneous quantification. Mycotoxins had a good linear relationship within a certain concentration range with correlation coefficients (r2) larger than 0.991 as well as the limit of quantitation of 1.80–300 μg/kg. The average recoveries at three different levels of low, medium and high fortification were 61–111% with relative standard deviations less than 13.5%. The method was fast, accurate, and suitable for the precise qualification of multiple mycotoxins in broiler tissues. 15 μg/kg zearalenone (ZEN) was detected in one liver sample among 30 samples from markets including chicken breast meat, liver, and gizzards. The result illustrated that the pollution of ZEN should not be neglected considering its harmful effect on the target organ of liver.

Systematic Study on a Quantitative Analysis of Multicomponents by Single Marker (QAMS) Method for Simultaneous Determination of Eight Constituents in Pneumonia Mixture by UPLC-MS/MS

Pneumonia mixture was formulated and is available to treat children acute pneumonia and acute bronchitis in our hospital for nearly forty years, but there are few studies of its quality evaluation or control. In this paper, a new strategy for quality evaluation of pneumonia mixture was explored and verified through qualitative and quantitative analyses of multicomponents by single marker (QAMS) by UPLC-MS/MS. Baicalein was selected as an internal reference, and the relative correction factors (RCFs) and the relative retention time (RRT) of (R, S)-goitrin, amygdalin, chlorogenic acid, pseudoephedrine hydrochloride, ephedrine hydrochloride, ammonium glycyrrhizinate, and baicalin were established. The robustness and durability of the QAMS method were investigated. RCF values calculated by the average (AVG) method and linear regression (LRG) method had good repeatability and were acceptable for quantitative analysis, and the RTT combined with the exact masses of precursor and fragment ions and their abundance could be adopted for accurately positioning the chromatographic peak of the eight constituents. The consistency and feasibility of the QAMS method were verified by comparing the contents of the seven components calculated by a classic and validated external standard method (ESM) with those of the QAMS method, which reduces analytical cost and time of detection and avoids the problem of the diversity and large quantity of reference standards. The results demonstrated that the QAMS method developed in this paper could provide a new, alternative, and promising method to comprehensively and effectively determine multicomponents and control the quality of pneumonia mixture or even a group of similar medicines.

Innovative Internal Standard Method Quality Control of Alcohol Products. Comparative analysis

Для обеспечения надлежащего качества и безопасности алкогольной продукции перед поставкой ее потребителям выполняется определение количественного содержания летучих компонентов. Данный контроль выполняют на газовых хроматографах. Количественный расчет значений концентраций выполняют по методу внешнего стандарта и по методу внутреннего стандарта. Метод внешнего стандарта используется в межгосударственных стандартах: ГОСТ 30536-2013, ГОСТ 31684-2012, ГОСТ 33833-2016, ГОСТ 33834-2016, ГОСТ 33408-2015, ГОСТ 31684-2012 и в государственных стандартах ГОСТ Р 52363-2005 и СТБ ГОСТ Р 51698-2001. С целью достижения высокой достоверности получаемых данных при контроле качества и безопасности алкогольной продукции, уменьшения материальных, финансовых и трудовых затрат предложен инновационный метод, заключающийся в использовании этилового спирта, содержащегося в испытуемом образце, в качестве внутреннего стандарта. Эффективность метода продемонстрирована на примере сравнительного анализа результатов определения количественного содержания летучих компонентов в широком спектре алкогольной продукции, выполненного по используемому в настоящее время методу внешнего стандарта и по предложенному методу. Показано, что для валидации метода и последующего его внедрения в практику испытательных лабораторий не требуется каких-либо дополнительных материальных, финансовых или трудовых затрат. To ensure the proper quality and safety of alcoholic beverages, the quantitative content of volatile compounds is determined before delivery to consumers. This control is performed on gas chromatographs. The quantitative calculation of the concentration values is carried by external and internal standard methods. The external standard method is used in standards: GOST 30536-2013, GOST 31684-2012, GOST 33833-2016, GOST 33834-2016, GOST 33408-2015, GOST 31684-2012 and in state standards GOST R 52363-2005 and STB GOST R 51698-2001. In order to achieve high reliability of the data obtained when controlling the quality and safety of alcoholic beverages, and to reduce material, financial and labor costs, an innovative method is proposed. This method is based on using ethyl alcohol, contained in the test sample, as an internal standard. The effectiveness of the method is demonstrated by the example of a comparative analysis of the results of determining the quantitative content of volatile compounds in a wide range of alcoholic beverages, performed according to the currently used external standard method and according to the proposed method. It is shown that for validation the method and its subsequent implementation into the practice of testing laboratories does not require any additional material, financial or labor costs.

Application of fingerprint combined with quantitative analysis and multivariate chemometric methods in quality evaluation of dandelion ( Taraxacum mongolicum )

A quality assessment method based on quantitative analysis of multi-components by single marker (QAMS) and fingerprint was constructed from 15 batches of dandelion ( Taraxacum mongolicum ), using multivariate chemometric methods (MCM). MCM were established by hierarchical cluster analysis (HCA) and factor analysis (FA). HCA was especially performed using the R language and SPSS 22.0 software. The relative correction factors of chlorogenic acid, caffeic acid, p-coumaric acid, luteolin and apigenin were calculated with cichoric acid as a reference, and their contents were determined. The differences between external standard method (ESM) and QAMS were compared. There was no significant difference ( t -test, p > 0.05) in quantitative determination, proving the consistency of the two methods (QAMS and ESM). Dandelion material from Yuncheng, Shandong was used as a reference chromatogram. The fingerprints in 15 batches of dandelion were established by HPLC analysis. The similarity of the fingerprints in different batches of dandelion material was greater than or equal to 0.82. A total of 10 common peaks were identified. This strategy is simple, rapid and efficient in multiple component detection of dandelion. It is beneficial in simplifying dandelion's quality control processes and providing references to enhance quality control for other herbal medicines.

Establishment of the Quantitative Analysis of Multiindex in Euphorbia lathyris by the Single Marker Method for Euphorbia lathyris Based on the Quality by Design Concept

Methods. The influences of methanol proportion, flow rate, column temperature, and injection volume in the mobile phase on the chromatographic resolution of chromatographic peak of euphorbia factor L1 were experimentally studied via Plackett–Burman design, and the key analysis parameters were screened out; the key analysis parameters were optimized through the central composite design, and the chromatographic analysis conditions were established. Euphorbia factor L1 was taken as the internal reference to construct the relative correction factors for L3 and L4 relative to L1, and their contents were calculated, thus realizing the QAMS. Meanwhile, the euphorbia factor L3 and euphorbia factor L4 were determined using the external standard method, and the differences of values measured by the external standard method from the values predicted by the QAMS method were compared, in an effort to verify the accuracy and feasibility of the QAMS method. Results. The methanol proportion and column temperature in the mobile phase were the key analysis parameters P < 0.05 , and the chromatographic conditions were determined as follows. The methanol/water ratio, column temperature, detection wavelength, flow rate, and injection volume were 60 : 40, 30°C, 275 nm, 1.0 mL/min, and 10 μL, respectively. A total of 20 batches of samples were determined by the QAMS method and external standard method; the relative standard deviations (RSDs) of L3 and L4 determination results were less than 2.0%, without any significant difference. Conclusion. The QbD-based QAMS method can be used to determine the contents of euphorbia factor L3 and euphorbia factor L4 in Euphorbia lathyris L., and it is accurate and feasible.

A Practical Method for Determination of Nine Nucleosides in Tricholoma matsutake by UPLC/MS and Quantitative Analysis of Multicomponents Using Single Marker Method

Nucleosides can be used as quality evaluation indicators of Tricholoma matsutake. In this work, a new ultra-performance liquid chromatography-tandem mass spectrometry (UPLC/MS) strategy for quantitative analysis of multiple components using a single marker (QAMS) was proposed to determine nine nucleosides (adenosine, cytidine, guanosine, inosine, uridine, 2′-deoxyadenosine, 2′-deoxycytidine, 2′-deoxyguanosine, and 2′-deoxyuridine) in T. matsutake. Guanosine was set as the internal reference substance, whose content in T. matsutake was determined using the conventional external standard method. Relative correction factors (RCFs) between guanosine and eight other nucleosides were measured. The concentrations of the eight components were calculated with the obtained RCFs by QAMS. An ultrasonic extraction method is used for sample preparation. This method was validated to be sensitive, precise, and accurate with the LODs of 0.31–1.9 ng, the overall intraday and interday variations less than 4.08%, and the overall recovery over 89.0%. The correlation coefficients (r2) of the calibration curves were higher than 0.9918. The values of vector angle analysis were above 0.99845, which indicates no significant differences between the conventional external standard method and the present QAMS method. As far as we know, this is also the first report of UPLC/MS analysis of nucleoside compounds by QAMS, providing an efficient and feasible quality assessment method for other natural products containing nucleosides.

1 An HPLC-MS/MS Method Using a Multitoxin Clean-up Column for Analysis of Seven Mycotoxins in Aquafeeds

Background In Guangdong Province of China, the climate here is very wet, so there are many different fungus living in the aquatic feeds, which produce mycotoxins. These compounds contaminate agriculture products world-wide and represent a great threat to human health. It is necessary to determine their contamination level in aquatic feeds. Objective A high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method was developed for the quantitative analysis of aflatoxin B1, aflatoxin M1, T-2 toxin, HT-2 toxin, deoxynivalenol, ochratoxin, and zearalenone in the fish and shrimp feed. Methods Samples were extracted with acetonitrile-water (V: V = 3:1), and degreased with acetonitrile-saturated hexane. Such obtained extract was cleaned up with a multitoxin column. The target compounds were separated on a C18 chromatographic column and analyzed simultaneously by electrospray ionization mass spectrometry in both positive or negative ion mode. Detected compounds were quantified by using the matrix-matched external standard method. Results Under the optimized conditions, good linearities for the analytes in corresponding concentration range were obtained with correlation coefficients (r2) higher than 0.9948. LOD ranged from 1.83 to 12.63 μg/kg, and LOQ ranged from 5.49 to 37.89 μg/kg. Average recoveries for the target mycotoxins at three spiked levels ranged from 80.5% to 116.5% with RSD ranging from 2.4% to 10.4%. 23 real aquafeed samples were determined by this method, and 7 kinds of toxins were all detected. Conclusions Obtained results showed that developed method could be successfully applied for the simultaneous determination of mycotoxins in aquatic feeds.