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2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maurelio Cabo ◽  
Prabhakar M. N. ◽  
Jung-il Song

AbstractThis study aimed to produce a new potential flame retardant thermoset resin from epoxidised corn oil through a one-pot method using liquid inorganic catalysed with hydrogen peroxide. Using a gas chromatography–mass selective detector, attenuated total reflectance-fourier transform infrared spectroscopy, proton nuclear magnetic resonance imaging, optical microscopy, and scanning emission microscopy, we synthesised a bio-based resin based on newly designed parameters. The flame retardant capacity was fully established using thermogravimetric analysis and a micro calorimeter. The produced epoxidised corn oil had a relative percentage conversion of oxirane of approximately 91.70%, wherein the amount of double bonds converted into epoxides was calculated. A significant reduction from 17 to 40% in peak heat rate release (pHRR) and 26–30% in total heat release was observed, confirming its flame retardant property. Thus, the potential of epoxidised corn oil was demonstrated.


Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6483
Author(s):  
Eridiane da Silva Moura ◽  
Lêda Rita D’Antonino Faroni ◽  
Fernanda Fernandes Heleno ◽  
Alessandra Aparecida Zinato Rodrigues

Essential oils (EOs) are widely recognized as efficient and safe alternatives for controlling pest insects in foods. However, there is a lack of studies evaluating the toxicological stability of botanical insecticides in stored grains in order to establish criteria of use and ensure your efficiency. The objective of this work was to evaluate the toxicological stability of basil essential oil (O. basilicum) and its linalool and estragole components for Sitophilus zeamais (Motschulsky) adults in corn grains by fumigation. The identification of the chemical compounds of the essential oil was performed with a gas chromatograph coupled to a mass selective detector. Mortality of insects was assessed after 24 h exposure. After storage for six (EO) and two months (linalool and estragole) under different conditions of temperature (5, 20, and 35 °C) and light (with and without exposure to light), its toxicological stability was evaluated. Studies revealed that the essential oil of O. basilicum and its main components exhibited insecticidal potential against adults of S. zeamais. For greater toxicological stability, suitable storage conditions for them include absence of light and temperatures equal to or less than 20 °C.


Author(s):  
Rukiye Oztekin ◽  
Delia Teresa Sponza

The objective of the study was the treatment of the pollutants (dissolved chemical oxygen demand (CODdis), total organic carbon (TOC) and total and individual polycyclic aromatic hydrocarbons (PAH)) present in the petrochemical industry wastewater (PCI) by sonication. The effects of increasing sonication times (0 min, 60 min, 120 and 150 min), sonication temperatures (25oC, 30oC and 60oC), on the CODdis, TOC and (PAH) removal efficiencies were researched at a sonication frequency of 35 kHz and a sonication power of 640. All the PAHs and their metabolites were measured by an gas chromatography (Agilent 6890 NC) equipped with a mass selective detector (Agilent 5973 inert MSD) with a capillary column (HP5-MS, 30 m, 0.25mm, 0.25µm)). The CH4, CO2 and H2 gas analysis, CODdis, TOC and the other pollutants were measured according to Standard Methods. As the sonication time and temperature were increased from 60 to 120 and 150 min, and from 25oC to 30oC and to 60oC, the CODdis, total PAH and TOC yields increased from 80.16% to 92.15%, from 78.37% to 94.23% and from 79.65% to 96.90%, respectively. The PAHs intermediates namely, 1–methylnaphthalene, 9–hydroxyfluorene, 9,10–phenanthrenequione, benzoic acid, 1,2,3–thiadiazole–4–carboxylic acid, naphthalene, p–hydroxybenzoic acid, fluorene, di–hydroxy pyrene, pyrene di–hydrodiol were sonodegraded with yields of 92.11%, 95.23%, 98.42%, 97.34%, 99.44%, 96.30%, 99.36%, 97.17%, 99.63% and 99.98% respectively, after 150 min, at 25oC. The presence of CH4, H2 and CO2 gases during sonication showed that the degradation mechanism of the PAHs is ‘‘pyrolysis”.


2021 ◽  
Vol 14 (3) ◽  
pp. 149-155
Author(s):  
А. А. Vinokurova ◽  
M. A. Hofenberg ◽  
V. A. Bagin ◽  
S. G. Dubrovin ◽  
V. A. Rudnov

The aimof our study was to evaluate the safety of ropivacaine given to lactating patients as a continuous infusion according to the selected local continuous wound infiltration (CWI) protocol after cesarean section (CS). Materials and methods.Elective CSs were performed under spinal anesthesia with bupivacaine 5% -2 ml at the L2L3 level. At the end of the operation, a 22 cm multiperforated catheter was placed in the surgical wound under the aponeurosis. 3 hours after spinal anesthesia a loading dose 8 ml of 0.2% ropivacaine was administered and followed by continuous infusion at rate 4 mL/h for 48 hours. Aside from CWI, all patients received systemic anesthesia: acetaminophen 4000 mg per os, ketorolac 90 mg IV and rescue opioid tramadol up to 400 mg (as-needed) daily. Breast milk (colostrum) samples were collected after 24 and 48 hours after a loading dose and were analyzed by gas chromatography with a mass selective detector for total ropivacaine concentrations. Results.The number of patients included in the study was 8. During the study neither cases of the onset of symptoms associated with systemic toxicity of ropivacaine, nor allergic and infectious complications, were observed. The mean +- SD Cmax total colostrum ropivacaine concentration was 0.005 0.002 (0.002 0.007) g / ml. Conclusion.In this limited sample, increasing the concentration or/and infusion rate seems to be a safe (for both mother and newborn) alternative or adjunct to standard systemic analgesia after CS in order to provide proper postoperative pain control.


2021 ◽  
pp. 785-799
Author(s):  
S. Shkurdoda ◽  
D. Shynkarenko ◽  
V. Pasichnyk ◽  
K. Korol ◽  
O. Posilskyi

The article deals with the recommendations for the detection of isoniazid in meat products, using the example of minced meat using physicochemical methods. This study does not lose its relevance over the years, due to the use of drugs for tuberculosis for poisoning homeless and domestic animals, in particular dogs, in different regions of Ukraine, the main active ingredient of which is isoniazid. The article describes a method for the extraction of isoniazid in food products of meat origin (minced meat, sausage), which presumably could or may be used to poison domestic animals, in particular dogs. Isoniazid was identified by the methods of qualitative color reactions, thin-layer chromatography, and gas chromatography with a mass-selective detector. The process of qualitative identification of isoniazid in foodstuffs that could or may be used to poison domestic animals, in particular dogs, includes: -the method of extraction and separation of interfering impurities, primarily fats, preliminary research by the method of qualitative analytical reactions; -studies by thin layer chromatography; -research by instrumental methods, in particular, gas chromatography with mass-selective detection. The method for extracting isoniazid from meat products described in the article is effective and allows you to get rid of interfering substances, especially fats. In addition, the method of gas chromatography with mass-selective detection has sufficient sensitivity and selectivity. It allows with a minimum number of interfering peaks of low intensity, determine the composition of isoniazid accurately. The specified list of instrumental base, methods and research techniques is not exhaustive. The examiner should be guided by the availability of relevant literature and the availability of appropriate analytical equipment (gas chromatograph, gas chromatograph with mass-selective detector, liquid chromatograph, liquid chromatograph with mass-selective detector, etc.). In accordance with this, it is necessary to use certain methods for studying substances. These methods are subject to mandatory verification before being used in the laboratory. The obtained research results allow us to recommend this technique for implementation in expert practice.


2020 ◽  
Vol 99 (10) ◽  
pp. 1159-1164
Author(s):  
Salim F. Shayakhmetov ◽  
Olga M. Zhurba ◽  
Anton N. Alekseenko ◽  
Alexey V. Merinov

Introduction. The presence of highly toxic polycyclic aromatic hydrocarbons (PAHs) in the production of aluminum and organochlorine compounds (OCC) in the production of polyvinyl chloride (PVC) poses a serious threat to the health of workers, necessitates biological monitoring of toxicants and their metabolites in biological media to assess health risks on basis of modern methods chemical analysis. Material and methods. Biomonitoring studies of the content of marker metabolite OCC - thiodiacetic acid (TDAA) in urine were performed in 65 workers of PVC production and PAHs metabolite - 1-hydroxypyrene (1-OHPyr) in 144 workers of the aluminum smelter using developed own methods of gas-chromato-mass-spectrometric (GC-MS) analysis. Sample analysis was performed on an Agilent 7890A gas chromatograph with an Agilent 5979 mass selective detector. Results. Methodological methods and parameters of GC-MS measurement of TDAA and 1-OHPyr in urine, which provided high selectivity and sensitivity of the analysis of samples, were examined and considered. Reliable differences in the levels of marker metabolites among the groups of main and auxiliary occupations and persons in the control groups, their dependence on the degree of exposure to PAHs, and OCC were established. The highest concentrations of TDAA in urine were observed in unit operators of PVC workshop and 1-OHPyr - in anode workers of aluminum production. Discussion. The revealed reliable intergroup and interindividual differences in the contents of TDAA and 1-OHPyr in the urine of workers indicate the reliability and informativeness of the results of the analysis of biological media. The results are consistent with data from foreign studies, confirm the occupational - production nature of the exposure of toxicants among workers in the main professions of enterprises. Conclusion. The results of approbation of highly sensitive and selective methods for the determination of TDAA and 1-OHPyr in urine samples developed on the base of GC-MS method demonstrate the possibility of their use in biomonitoring studies of workers of productions and the population to adequately assess the exposure of highly toxic PAHs and OCC.


2020 ◽  
Vol 7 (1) ◽  
pp. 7
Author(s):  
Noor Erma Nasution Sugijanto ◽  
Citra Hayu Adi Makayasa ◽  
Gita Deseria ◽  
Rahmania Alrika Ilma Bridgeta ◽  
Miftakhul Rohmah Putri ◽  
...  

Pendahuluan: Kacang tolo (Vigna unguiculata L. Walp.) merupakan polong-polongan multiguna dapat berfungsi sebagai hipokolesterolemik. Kacang tersebut mengandung protein tinggi dan rendah lemak, sebagai bahan makanan dikonsumsi dengan cara direbus maupun digoreng. Tujuan: Penelitian ini bertujuan untuk mengidentifikasi komposisi fitosterol pada kacang tolo yang mentah, direbus, dan digoreng serta mengidentifikasi pengaruh proses perebusan dan penggorengan kacang tolo terhadap komposisi fitosterol. Metode: Seluruh sampel diperoleh dari Pasar X, Y, dan Z, area Jawa Timur. Masing-masing sampel diekstraksi dengan n-heksana, aseton, dan kloroform kemudian dianalisis dengan Kromatografi Lapis Tipis (KLT), Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR), Kromatografi Gas-Flame Ionization Detector (KG-FID), dan Kromatografi Gas-Mass Selective Detector (KG-MSD). Hasil: Analisis KLT dan ATR-FTIR menunjukkan adanya kandungan fitosterol pada kacang tolo. Analisis dengan KG-FID menunjukkan adanya kolesterol, kampesterol, stigmasterol, dan sitosterol pada kacang tolo mentah dan direbus dari Pasar X, Y, dan Z sedangkan kacang tolo yang digoreng dari Pasar X hanya mengandung stigmasterol dan sitosterol. KG-MSD menunjukkan adanya kolesterol, kampesterol, stigmasterol, dan sitosterol pada kacang tolo mentah, direbus, dan digoreng. Kesimpulan: Kacang tolo mentah, direbus, dan digoreng dapat diidentifikasi adanya ke-empat fitosterol, yaitu kolesterol, kampesterol, stigmasterol, dan β-sitosterol. Proses perebusan dan penggorengan kacang tolo berpengaruh terhadap komposisi fitosterol.


Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2781 ◽  
Author(s):  
Eridiane da Silva Moura ◽  
Lêda Rita D’Antonino Faroni ◽  
Fernanda Fernandes Heleno ◽  
Alessandra Aparecida Zinato Rodrigues ◽  
Lucas Henrique Figueiredo Prates ◽  
...  

The essential oil of basil (Ocimum basilicum) has significant biological activity against insect pests and can be extracted through various techniques. This work aimed to optimize and validate the extraction process of the essential oil of O. basilicum submitted to different drying temperatures of the leaves and extracted by the combination of a Clevenger method and ultrasound. The biological activity of the extracted oil under different conditions was evaluated for potential control of Sitophilus zeamais. The extraction method was optimized according to the sonication time by ultrasound (0, 8, 19, 31 and 38 min) and hydrodistillation (20, 30, 45, 60 and 70 min) and drying temperature (20, 30, 45, 60 and 70 °C). The bioactivity of the essential oil was assessed against adults of S. zeamais and the effects of each variable and its interactions on the mortality of the insects were evaluated. The best yield of essential oil was obtained with the longest sonication and hydrodistillation times and the lowest drying temperature of leaves. Higher toxicity of the essential oil against S. zeamais was obtained by the use of ultrasound for its extraction. The identification and the relative percentage of the compounds of the essential oil were performed with a gas chromatograph coupled to a mass selective detector. The performance of the method was assessed by studying selectivity, linearity, limits of detection (LOD) and quantification (LOQ), precision and accuracy. The LOD and LOQ values for linalool were 2.19 and 6.62 µg mL−1 and for estragole 2.001 and 6.063 µg mL−1, respectively. The coefficients of determination (R2) were >0.99. The average recoveries ranged between 71 and 106%, with coefficient of variation ≤6.4%.


2020 ◽  
Vol 22 (1) ◽  
pp. 113-122
Author(s):  
R. Alani ◽  
K. Olayinka ◽  
B. Alo

Contamination of Lagos soils with persistent, bioaccumulative and toxic micropollutants (PBTs) may not only affect the non-target species residing in the soil, but also raises the concern of the possibility of the chemicals finding their way into the Lagoon and other water courses via soil run-off and leaching. In this study, soil samples were collected from three busy areas of Lagos (Apapa, Okobaba and Iddo) and analyzed for Polychlorinated Biphenyls (PCBs), Organochlorine pesticides (OCS), and Polycyclic Aromatic Hydrocarbons (PAHs). Gas Chromatography with Mass Selective Detector (GC/MSD) was used for the analyses. Iddo had the highest percentage organic carbon content of 39.39% with highest total PAHs of 2,706.93 ng/g. The highest total PCBs of 23.63 ng/g was found at Apapa 3 which was one of the three sampling points in Apapa. PCB 74 was the onlyPCB found in all the soil samples and ranged between 3.55 ng/g and 23.64 ng/g at Apapa 1 and Apapa 2 respectively. High concentrations of the following organic compounds were also obtained at the following locations- naphthalene (1,625.10 ng/g) at Iddo; dichlorodiphenyldichloroethylene (p,p'DDE ), (117.98 ng/g) at Okobaba, and PCB 74 (23.63 ng/g) at Apapa 1. The results obtained showed that the higher the municipal activity, the higher the percentage organic carbon content. Key words: Bioaccumulative and toxic micropollutants, Gas chromatography/Mass selective detector, Persistent organic carbon, Soil organic pollutants


2019 ◽  
pp. 168-176
Author(s):  
Anastasia Semenova ◽  
Andrey Ivankin ◽  
Tatyana Kuznetsova ◽  
Andrei Dydykin ◽  
Viktoria Nasonova ◽  
...  

The paper presents a study of Moskovskaya cooked smoked sausages formed in various artificial casings: fibrous (cellulose), collagen, and polyamide. An oxygen permeability oxygen permeability of the casings was above 40 cm3 and below 30 cm3/m2∙24 h∙bar. The study involved a sensory evaluation and instrumental tests using a VOCmeter multi-sensor system (‘electronic nose’) and a 7890A gas chromatograph with a 5975C VLMSD mass-selective detector (Agilent Technologies). We obtained original data on the qualitative composition and the quantitative content of substances that form the aroma of cooked smoked sausages in various types of casings. We found that the samples contained two groups of compounds with the chemical formulas of C H O i k l and C H O N . i k l m They had a ratio of (12–33):1 and were, apparently, the most significant aromatic substances. The main class of identified compounds was carboxylic acid esters, accounting for 76.61–81.60% of the total substances. We established a correlation between the aroma intensity and the concentration of chlorine-containing and nitrogen-containing compounds (except amines, amides, nitriles, and hydrazides) in the gas phase. The results did not confirm our hypothesis about the influence of the casing type and its permeability on the development of oxidative processes in the production of cooked smoked sausages. The practical significance of the study lies in creating a database of over 200 aromatic compounds that allows for a deeper understanding of aroma formation processes in cooked smoked sausages. The database can be used to exert a purposeful technological influence on the quality indicators and create various flavour compositions to adjust the sensory properties of the product.


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