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Abstract

An ion chromatographic method and its application have been described to quantify nine cationic components (lithium, sodium, ammonium, methylammonium, potassium, magnesium, calcium, strontium, and barium) in pyrotechnics (firecracker and firework) samples. The samples in this study were purchased from local shops in Ternate City, North Maluku. The method performed a mixed eluent with 4 mM HNO3 and 0.015 mM Na2EDTA, combined with a Metrosep C4-150/4.0 separation column for all quantifications. Excellent chromatograms were achieved, and the nine cationic components were eluted in less than 18 min. The calibration graphs of the quantifications were linear in the range of 1.25–37.5 mg L−1. The detection limit (LOD) at S/N = 3 was below 0.098 ppm (mg L−1). This method was applied to the pre-blast and post-blast residues of pyrotechnics samples, and the simultaneous quantification of the nine cationic components in these samples was achieved with satisfactory results.

Open access

A talajspektrális könyvtárak nemzetközi jelentősége és hazai megalapozása

The international importance and national establishment of soil spectral libraries

Agrokémia és Talajtan
Authors:
Ádám Csorba
,
Tamás Szegi
,
Gábor Várszegi
,
Gábor Nagy
, and
Erika Michéli

Napjainkban soha nem látott igény mutatkozik megfelelő mennyiségű és minőségű talajadatra és információra. Spektroszkópiai technológiák a hagyományos laboratóriumi módszerekkel együttesen, párhuzamosan alkalmazva lehetőséget kínálnak a talajfelvételezés idő- és költséghatékonyabbá, valamint környezetkímélőbbé tételére. Jelen munkában lokális, regionális és globális léptékű talajspektrális könyvtárak bemutatása mellett az első országos szintű, az Agrártechnológiai Nemzeti Laboratórium projekt keretében kidolgozásra kerülő, Magyarország talajtani változatosságát reprezentáló spektrális adatbázis létrehozásának koncepcióját mutatjuk be. A spektrális könyvtárak olyan speciális talajadatbázisoknak tekinthetőek, melyek tartalmazzák egy adott terület talajait reprezentáló talajminták hagyományos laboratóriumi módszerrel meghatározott paramétereit, valamint spektroszkópiai módszerrel rögzített spektrumait. A spektrális könyvtárakban tárolt adatok alapján elvégzett, spektroszkópiai kalibrációkra alapozott talajparaméter becslési eljárások lehetőséget kínálnak az adatbázisban szereplő talajminták fizikai-kémiai-ásványtani tulajdonságaihoz hasonló minták paramétereinek spektrális alapú megbízható megbecsléséhez. A hazai spektrális könyvtár alappillérét a Talajvédelmi Információs és Monitoring (TIM) rendszer mintavételezés kezdeti évében (1992-ben) gyűjtött, talajok genetikai szintjeiből vett talajmintákról felvett spektrumokra építjük. A spektrális adatbázist a középső-infravörös (middle-infrared, MIR), valamint a látható- és közeli infravörös (visible and near-infrared, VIS-NIR) tartományban, a Global Soil Laboratory Network (GLOSOLAN) iránymutatásai alapján rögzített spektrális adatokra építjük. A folyamatosan bővülő spektrális könyvtár, és az erre az adatbázisra épülő talajtulajdonság-becslő eljárás lehetőséget fog kínálni számos fizikai és kémiai paraméterének megbízható meghatározására, ezzel (számottevő többletköltség nélkül) nyújt lehetőséget a jelenlegi laboratóriumi kapacitás növelésére.

Open access

Abstract

An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of nobiletin and tangeretin in rat plasma, and the plasma was processed by a simple liquid-liquid extraction method with ethyl acetate. The chromatographic column was UPLC HSS T3 (50 × 2.1 mm, 1.7 μm), the mobile phase was acetonitrile-water (containing 0.1% formic acid). Multiple reaction monitoring mode (MRM) was used for quantitative analysis, nobiletin m/z 403.29 → 373.14 (cone voltage 22v, collision voltage 28v), tangeretin m/z 373.28 → 343.17 (cone voltage 20v, collision voltage 28V), tangeretin m/z 373.28 → 343.17 (cone voltage 20V, collision voltage 28V) and internal standard vitexin m/z 433.14 → 313.03 (cone voltage 32v, collision voltage 26v). The pharmacokinetics of nobiletin and tangeretin were evaluated in rats. The established UPLC-MS/MS method in the range of 2–2,000 ng mL−1 was successfully applied to the pharmacokinetics, and the calculated bioavailability of nobiletin and tangeretin was 63.9 and 46.1%, respectively.

Open access

Abstract

Based on chromatographic fingerprinting combined with quantitative analysis on characteristic chemical constituents as well as hierarchical cluster analysis, an easy and sensitive approach utilizing high performance liquid chromatography (HPLC) was developed for the identification and quality evaluation of Rutongshu oral liquid (ROL). What is more, nontargeted metabolomic analysis was conducted to gain a global view in terms of its chemical profile. In this study, 16 peaks from different batches (S1–S10) of ROL samples produced by Taihe Hospital of Chinese Medicine were selected as common peaks for the evaluation of their similarity whose values of all tested 10 batches exceeded 0.90 when compared with the control fingerprints. Meanwhile, simultaneous quantification of five markers in the oral solution, including albiflorin, paeoniflorin, chlorogenic acid, quercetin and ferulic acid was performed, and standard curves established for respective reference substances showed good regression in the linear range (r 2 > 0.999) with recoveries in the range of 98.96–102.35%. The ultra-high performance liquid chromatography (UHPLC) combined with Orbitrap Exploris 120 mass spectrometer resulted in 88 identified compounds. The results of validation showed that the established method was reproducible, precise and stable. This study offers an effective, dependable and useful approach for the systematic evaluation of the hospital formulation ROL.

Open access

Abstract

Hydrochlorothiazide has been utilized clinically for the past half-century, which is popularly known as a “water pill” as it produces increased urine output. The advancement of bioanalytical methods brought a dynamic field with exciting opportunities for future research. The current review emphasis the bioanalytical methods employed for the quantitative estimation of Hydrochlorothiazide as monotherapy and its popularly used combinational medications available from 1956 to till date. A fixed dose of 25 mg of hydrochlorothiazide with 43 combinational medications is currently available in the market and these combinations are widely employed in the treatment of hypertensive people; those whose blood pressure does not respond effectively to monotherapy of hydrochlorothiazide and also for the treatment of edema (excess fluid in the body) caused by illness such as heart failure, liver problems, and renal disease. It has been convincingly demonstrated that the combination of any two antihypertensive medications belonging to different groups of the same category, significantly lowers blood pressure, in comparison with the effect produced by increasing the dose of a single medicament. Among the various analytical techniques employed for the estimation of Hydrochlorothiazide, the review portrays that hyphenated technique, in specific liquid chromatography coupled with mass spectroscopy was widely employed. The validation parameters namely linearity, LOD, LOQ for individual drug and their combinations, were successfully calibrated. The effectiveness of analytical approaches was evaluated and enhanced for chemical factors. The involvement of green chemistry in the optimized methods for the evaluation of Hydrochlorothiazide for the future development, are suggested.

Open access

Abstract

This review focuses on monosodium glutamate which proclaims the fifth taste as “Umami”. Monosodium glutamate imparts a deep, meaty, umami flavour to foods. Asian cuisine frequently uses this flavouring, just as in the processed items produced across the United States and Europe. This article dealt with a detailed discussion of physicochemical features, pharmacological actions, and different reported analytical methodologies for the estimation of monosodium glutamate. Monosodium glutamate is analyzed using a variety of techniques, including spectroscopy, chromatography, electrochemistry, electrophoresis, chemometrics, flow injection analysis, and biosensors. According to results of comparative research of analytical methodologies, high performance liquid chromatography (HPLC) is most widely used method for analyzing monosodium glutamate which surpasses the gas chromatographic (GC) approach. All of the reported methods are accurate, precise, cost-effective, and sensitive. The European Union defined monosodium glutamate as a food additive that is permitted in some foods, but is subject to quantitative limits. Consequently, this study provides the analyst with an accessible path to quantifying monosodium glutamate's content for use in the food and pharmaceutical industries.

Open access

Abstract

A straightforward, dependable, and quick RP-LC method for the analysis of abiraterone acetate in its dose form and human urine has been devised. With DAD detection, sensitivity was reported to be high. The LOD and LOQ of the procedure were deemed adequate. The suggested approach was exhaustively validated in accordance with ICH requirements, and the findings demonstrated that it was exact, accurate, selective, and sensitive for the analysis of this pharmaceutical. The chromatographic separation was realized using a X-Terra RP-18 (150 × 4.60 mm i.d. × 5 μm) column and a UV detector set at 255 and 267 nm. In addition, pK a values were calculated based on the relationship between the retention factor and the pH of the mobile phase. The influence of the composition of the mobile phase on the ionization constant was investigated by measuring the pK a at various acetonitrile–water combinations ranging from 50 to 70% (v/v).

Open access

Abstract

Lenalidomide is a drug that has immune-modulating, anti-angiogenic, and anti-inflammatory properties. In this study, we developed green HPLC and spectrophotometric methods to determine the concentration of lenalidomide in pure and pharmaceutical formulations. In the HPLC method, 10 mM potassium dihydrogen phosphate solution (pH: 2.0) and ethanol (50:50, V/V) were used as mobile phases, isocratic elution was applied at a flow rate of 1.0 mL min−1 and detection was made at 304 nm. In the spectrophotometric method, the spectral patterns of standard solutions in different solvents were comprehensively examined, the best spectra were obtained with ultrapure water, and a wavelength of 304 nm was selected for detection. Both methods have been validated according to ICH guidelines for various parameters. Correlation coefficients greater than 0.999 were determined for both methods in the concentration range of 5–30 μg mL−1. The developed methods were applied to commercial formulations, and comparisons of the results were made using the Student (t) test for means and the Fischer (F) test for standard deviations. No statistically significant difference was observed between the methods. The greenness evaluation of these methods was carried out using AGREE software. The developed methods are proposed as excellent environmental and operator-friendly alternatives for the quantification of Lenalidomide in pharmaceutical formulations.

Open access

Abstract

“Feed the global population and regenerate the planet.”

The conditions necessary for the implementation of the above commonly used slogan did not exist 10–15 years ago. We did not have access to the information and databases that would have allowed us to increase yields for the purpose of feeding the growing population. While increasingly meeting sustainability requirements and regenerating the Earth. Anthropocentrism, the belief that humans are superior to everything else, benefits humans by exploiting human greed and ignorance, which is a dead end for both individuals and societies. Only humans can ignore the dynamic equilibrium processes of nature and disregard the consequences that adversely affect future generations. Ecocentric agricultural practices have several prerequisites. It is important for the academic sphere to recognize its significance. Another fundamental challenge is the continuous monitoring of the production unit and its close and distant environment for the purpose of decision preparation using Big Data. The Internet of Things (IoT) is a global infrastructure that represents the network of physical (sensors) and virtual (reality) “things” through interoperable communication protocols. This allows devices to connect and communicate using cloud computing and artificial intelligence, contributing to the integrated optimization of the production system and its environment, considering ecocentric perspectives. This brings us closer to the self-decision-making capability of artificial intelligence, the practice of machine-to-machine (M2M) interaction, where human involvement in decision-making is increasingly marginalized. The IoT enables the fusion of information provided by deployed wireless sensors, data-gathering mobile robots, drones, and satellites to explore complex ecological relationships in local and global dimensions. Its significance lies, for example, in the prediction of plant protection. The paper introduces small smart data logger robots, including the Unmanned Ground Vehicles (robots) developed by the research team. These can replace sensors deployed in the Wireless Sensor Net (WSN).

Open access

Abstract

Hungary is a Central European country that is rich in medicinal and aromatic wild plant species; in rural livelihoods, the collection, use, process, and trade of these plants are traditionally important contributors. However, due to several recent changes touching the sector, the natural ecosystems, biodiversity, and collectors - who generally belong to poorer social groups – are affected negatively.

The paper aims to introduce the Hungarian herbal sector from a holistic perspective, including its economic, environmental, and human dimensions, with a particular focus on sustainability. In this context, the purpose of the article is to discover this field as comprehensibly as possible and present it from both theoretical and practical aspects. Another objective is to collect the best practices and feasible solutions from the field in connection with promoting a harmonious, as well as economically prosperous relationship between nature and local people. This integrated approach helps show the industry's strengths and advantages, as well as its weaknesses and challenges. Based on the findings, the paper attempts also to propose some recommendations for the future.

Open access