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Chemical engineering is an engineering branch that deals with the chemical production and manufacture of products that undergo chemical processes. This includes equipment design, creating systems and processes to refine raw material, as well as mixing, compounding, and processing chemicals to create products.

Chemistry and Chemical Engineering

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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

„Két lábbal a földön, avagy miként próbál a talajtan válaszokat adni a globális kihívásokra”

Beszámoló a HUN-REN ATK Talajtani Intézetének Magyar Tudomány Ünnepe előadónapjáról

Agrokémia és Talajtan
Author:
Kitti Balog
Restricted access
Progress in Agricultural Engineering Sciences
Authors:
Donald Bimpong
,
Lois Amponsah Adofowaa
,
Ama Agyeman
,
Abena Boakye
,
Ibok Nsa Oduro
,
Ellis William Otoo
, and
John-Lewis Zinia Zaukuu

Abstract

Peanut butter and yoghurt are targeted for adulteration intended at consumer deception. This study aimed to fingerprint and detect peanut butter and yoghurt adulteration with cassava flour and starch using Near Infrared Spectroscopy (NIRS) in a quasi-experimental approach. Ingredients for laboratory sample preparation were obtained from the Kumasi Metropolis. Peanut butter was adulterated at 1, 3, 5, 10, 15, 20% w/w and yoghurt at 0.25, 0.5, 1, 3, 5, 10, 15, 20, 25, 45, 50% w/w. Selected concentrations mimicked practices on the market. Marketed products were randomly sampled from six markets in the Kumasi Metropolis to validate the study models. Samples were scanned with a hand-held NIRS in triplicates. Chemometric (Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Partial Least Square Regression (PLSR) models) statistical methods were employed to develop classification and prediction models. Peaks with spectral bands such as 1050 , 1200 and 1450 nm were observed for peanut butter and 990–1100 nm, 1100–1200 nm and 1300–1408 nm were observed for yoghurt in the NIR spectrum. Some yoghurt brands were suspected of containing cassava starch, while Peanut butter from the different markets differed based on classification models. Cassava flour and starch concentrations were quantitatively predicted by PLSR with an R2 CV of 0.98 and an error of 0.9 g/100 g (low error).

Restricted access

A talaj katabolikus aktivitás mintázatának elemzése mikrorespirációs (MicroResp) módszerrel

Analysis of soil catabolic activity patterns by micro-respiration (MicroResp)

Agrokémia és Talajtan
Authors:
Tibor Szili-Kovács
,
Márton Mucsi
,
Anna Füzy
,
Tünde Takács
, and
Andrea K. Borsodi

A talaj mikrobiális közösségének funkcionális diverzitása a talaj ökoszisztéma szolgáltatások jelentős részéhez hozzájárul, sok esetben meghatározó jelentőségű. Többféle kísérleti és elméleti megközelítés közül a katabolikus aktivitás-mintázat mikrorespirációs – MicroResp™ – módszerrel történő megközelítését mutatjuk be. A módszer a régebbről ismert szubsztrát-indukált respiráció több-szubsztrátos, mikrotiter lemez alapú kiterjesztése, amivel a talaj mikroba-közösség in-situ közösségi-szintű fiziológiai mintázata határozható meg. Mivel az egyes mikroorganizmusok szubsztrát-hasznosítása eltérő, a mikroba-közösség aktuális összetételétől, abundanciájától függően változó a szubsztrát hasznosítási mintázat egy-egy talajminta esetében. Az alkalmazott szubsztrátok köre tetszőleges, rendszerint egyszerű cukrok, aminosavak, aminok, karbonsavak. A módszer gyors, érzékeny, megbízható, ezért alkalmazása tervezett kísérletekben és talajmonitoring programokban egyaránt javasolható.

Open access

Abstract

The soaking step of dry pulse products' – e.g. chickpeas' – food processing is a time consuming process. Soaking time can be significantly reduced by ultrasonic treatment or using higher processing temperatures. The effect of ultrasonic treatment can be investigated by examining the soaking water characteristics. Ultrasound-assisted soaking of chickpeas was performed at 25, 35 and 45 °C, respectively. Additionally, control samples were also prepared without ultrasonic treatment at the same temperatures. The dynamics of the fitted curve clearly shows the relationship namely the higher the treatment temperature, the faster the hydration of the raw material for both untreated and treated groups. In contrast to control group, swelling rate of 2.00 – except the group 45 °C – is not achieved during ultrasound-assisted soaking. In case of treated group, the swelling rate was about 1.90 for all temperatures applied. The ANOVA test shows that the color of the ultrasonically treated samples was significantly different compared to the control (F (5;12) = 207.86; P < 0.001). Average dry matter content and °Brix value were significantly higher in the ultrasound treated group compared to the control in case of all temperatures. This may indicate the destructive effect of ultrasound, which may cause more components to dissolve out of the raw material by the end of the soaking process.

Open access

Abstract

The objective of our work was to analyze the differences between four nut pastes, which were the following: walnut, peanut, pistachio, and tahini (sesame). The process technology of them is unknown, however, all the products contain 100% nut without any additives or flavoring.

The paste samples were measured at 25 ± 0.2 °C. The apparent viscosity at a 10 1/s shear rate during flow curve recording, and the dynamic viscosity at a constant 20 1/s shear rate was determined by viscosity measurement with the use of the MCR302 modular compact rheometer. The L*a*b* color components were determined by ColorLite sph850 spectrometer, finally, the particle sizes and shapes of the samples were analyzed by the high-speed image analysis instrument QICPIC.

The apparent viscosity and the average dynamic viscosity values of the four nut pastes were significantly different from each other. Differences were found between each paste according to the L*a*b* parameters. The complex structures of the particles are detailed and measurable, whereby the lengths and diameters of the particles can reliably be determined and fine deviations between the samples are detected. The sphericity decreases slightly with increasing particle size which means that bigger particles are more irregularly shaped.

Open access
Acta Chromatographica
Authors:
Natalija Nakov
,
Liljana Anastasova
,
Marija Zafirova Gjorgievska
,
Jelena Acevska
,
Katerina Brezovska
,
Rumenka Petkovska
, and
Aneta Dimitrovska

Abstract

In this study, two different ethanol-based RP-HPLC methods for assay and quantification of rivaroxaban related substances in tablets were developed, based on green analytical chemistry (GAC) principles, using the design of experiments approach. The chromatographic separation was performed on X-Bridge C18 column (250 × 4.6 mm, 5 µm particle size), using isocratic elution with ethanol : water (35:65, % v/v) for the assay and gradient elution with ethanol/water mobile phase, for related substances, with a flow rate of 1.0 mL min−1. The gradient method was optimized for the separation of three specified impurities (impurity G, impurity H, and impurity 14) and the selectivity was further confirmed using forced degradation studies. Both methods were validated in accordance with ICH guidelines. The robustness of the methods was confirmed with the Central Composite Face Design of Experiments. Analytical Eco-scale approach and AGREE metrics confirmed that both methods are in accordance with the GAC principles. The proposed ethanol-based RP-HPLC methods were applied for assay and determination of related substances in rivaroxaban 10 mg tablets obtained from three different manufacturers available on the Macedonian market.

Open access