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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.

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The rice plant is sensitive to soil salinity. Calcium (Ca) acts as an ameliorative agent that helps plants induce salt tolerance. This study was carried out with a comparison of the ameliorative effect of calcium on salt-stressed rice seedlings, the determination of the role of salt-responsive protein groups, and the analysis of their genetic expressions in 21-day-old rice seedlings of ten locally cultivable varieties of West Bengal. For this study, 15-day-old seedlings were treated with 200 mM of sodium chloride (NaCl) solutions along with 10 mM of calcium sulfate (CaSO4) treatment. The determination of the relationship between the salt-responsive proteins and the analysis of the gene expression of those corresponding proteins were not carried out earlier on the selected ten locally cultivable rice varieties of West Bengal. The NaCl crystals were visible on the abaxial leaf surface of salt-stressed rice seedlings. The superoxide dismutase activity was increased in rice varieties, and a similar result was also expressed with calcium treatment. The fourier transform infrared spectroscopy-attenuated total reflection spectral result gave strong evidence for the presence of several salt-tolerant proteins and their genetic expression. STRING database results have suggested that the calcium treatment, coupled with the expression of the CBL4 protein, has regulated the P5CR protein of proline biosynthesis for better salt tolerance and osmotic protection. The quantitative real-time polymerase chain reaction and SDS-PAGE gel electrophoresis analysis showed that salt-tolerant varieties, Chinsurah_nona_1, and Jarava had high calcium signaling mechanisms and osmo-protection abilities.

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Abstract

The advection-convection models (ACM) have practical applications in the investigation of separation processes, where mass (heat) is transferred by convection and diffusion (dispersion) along mass/heat exchanger, eq. adsorption, chromatography column, tubular reactor, etc. The ACM consists of nonlinear partial differential equations which can be solved only with numerical methods. In the article, a comparison of the volume method (VM) and orthogonal collocation on finite elements (OCFE) is presented in terms of their reliability, accuracy of calculations, and speed of calculation. The OCFE proved to be more robust than VM.

The linear ACM model for the chromatography column has an analytical solution in the form of the equation for the number of theoretical plates (N). This equation is often applied in the interpretation and evaluation of model parameters. However, the versions of N equation published in the literature are not correct. The error can lead to significant imprecision for specific cases. Here, in the paper, the revised equations are presented and discussed for the most frequently used chromatography column models.

Open access

Abstract

This study attempted to optimize pectin extraction from queen pineapple (Qp) peels using microwave-assisted method. A three-factor factorial experimental design was employed to test the interaction of moisture content of pineapple peel, pH of the citric acid solution and extraction time. The three-way interaction among the factors has a significant effect on pectin recovery. Two-way interaction between moisture content and pH level, as well as pH level and extraction time caused significant difference in the pectin recovery. Pectin recovery increases with lower moisture content while longer extraction time does not significantly increase pectin recovery. The optimum combination of the parameters is 12% moisture content, pH level 2 of the citric acid solution, and extraction duration of 2 min, which yielded 1.01 ± 0.01% pectin recovery. This is lower than the results from previous studies on pineapple with 3.88–13.06% pectin recovery using acid extraction method. Hence further optimization is recommended.

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Abstract

Plant protection products (PPP), crucial for agricultural production, are experiencing increased global demand, particularly with the growing need for food production. To meet this demand, robust analytical methods are essential for confirming the presence and determining active substance concentrations in PPP. This study introduces an analytical method utilizing high-performance liquid chromatography with a diode array detector (HPLC-DAD) for determination of acetamiprid in water-soluble powder formulations. The method, validated according to SANCO/3030/99 rev.5, demonstrated exhibited adequate accuracy and precision, with repeatability expressed as the ratio of the standard deviation (% RSD) to the relative standard deviation (% RSDr) being lower than 1. Recoveries for the active substance at concentrations above 10% ranged from 97% to 103%. The developed method is also characterized by suitable linearity, confirmed by a correlation coefficient >0.99. Specific chromatographic profiles were generated, and acetamiprid content in 180 formulations was analyzed, including reference products. The developed method aligns with “green chemistry” principles, minimizing solvent use and emphasizing energy efficiency. Overall, it offers a comprehensive approach for qualitative and quantitative analysis, ensuring the reliability of PPP quality control.

Open access

Pilóta nélküli légi járművek alkalmazása a vizes élőhelyek modern felmérésében

Application of unmanned aerial vehicles as modern tools for wetland monitoring

Agrokémia és Talajtan
Authors:
Réka Döbröntey
,
János Grósz
,
Judit Rita Keleti
,
Tamás Szegi
,
Márta Fuchs
,
Erika Michéli
, and
Ádám Csorba

A vizes élőhelyek a vízi és a szárazföldi ökoszisztémák között elhelyezkedő, igen változatos, és általában nehezen lehatárolható területek. Kiemelt jelentőségük annak köszönhető, hogy bár csak a globális szárazföldi területek mintegy 6–7%-át borítják, kulcsfontosságú szerepet játszanak az éghajlat szabályozásában, a vizes ökoszisztémák biodiverzitásának és hidrológiai viszonyainak fenntartásában, valamint számos további ökológiai és társadalmi funkciót is szolgáltatnak, beleértve az árvízvédelmi, víztisztítási, szén-dioxid-tárolási, élőhelytámogatási és kulturális, rekreációs előnyöket. A vizes élőhelyek azonban mind természetes, mind antropogén hatások következtében térben és időben is dinamikusan változnak, ezért védelmük és megfigyelésük napjainkra igen fontos kutatási területté nőtte ki magát. A műholdas távérzékelés nagyobb területek egyidejű megfigyelését teszi lehetővé, azonban érzékeny a felhőzetre és a légköri hatásokra, bizonytalanságot okozva ezzel az eredményekben. A hagyományos monitoring technológiák mellett a pilóta nélküli légi járművek térnyerése egyre kifejezettebb, köszönhetően rugalmasságának, hatékonyságának és alacsony költségének, miközben nagy térbeli és időbeli felbontású, szisztematikus adatszolgáltatásra képes. Tanulmányunk a pilóta nélküli légi járművek alkalmazási lehetőségeibe nyújt betekintést a vizes élőhelyek felmérésében, valamint áttekinti és összehasonlítja az egyéb távérzékelés technológiák alkalmazhatóságát ezen területek megfigyelésében. Célja, hogy elősegítse a dróntechnológia további terjedését és széles körű alkalmazását a vizes élőhelyek monitorozásában.

Open access

Abstract

In this work, an assessment of effective solvents and extraction methods was carried out to recover the bioactive compounds from hawthorn fruit (Crataegus monogyna Jacq.). Extractions assisted by heat, microwave, and ultrasound were carried out using various organic solvents (methanol, ethanol, and isopropanol). pH differential, Folin–Ciocalteu's, and aluminum chloride methods were used to determine total monomeric anthocyanin (TMA), total phenolic compound (TPC), and total flavonoid content (TFC), consecutively. Ferric Reducing Antioxidant Power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl Hydrate (DPPH), and 2,2′- azino- bis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) assays were used to measure the antioxidant activity (AA) of the extracts. The outputs revealed that extraction methods and solvents significantly affect anthocyanin concentration, TPC, TFC, AA, and color values of hawthorn fruit extracts. Due to the highest recovered TMA (0.152 ± 0.002 mg ECy3Gl/g of dry weight), TPC (49.14 ± 0.38 mg gallic acid equivalents/g of dry weight), and TFC (18.38 ± 0.19 mg quercetin equivalents/g of dry weight) contents, the ultrasonic-assisted extraction is superior to heat and microwave-assisted extractions. Accordingly, it was also observed that the methanol solvent is more profound than ethanol and isopropanol. Further, the bioactive compounds' content and the extracts' antioxidant activity are shown to be highly correlated. Thus, hawthorn extracts are considered to have antioxidant properties because of their concentrated bioactive compounds.

Open access

Abstract

Venetoclax is the first oral Bcl-2 inhibitor with high affinity targeting tumor cell apoptosis mechanism. In this study we developed a simple, sensitive and reliable LC–MS/MS method to determine venetoclax in children's hemolytic or lipemic samples. The method utilized an electrospray ion source and operated in multiple reaction monitoring mode. Venetoclax-d8 was used as an internal standard. Plasma samples were precipitated by acetonitrile containing 10% dimethyl sulfoxide and were separated by a Hypersil GOLD column (2.1 mm × 150 mm, 5 μm). The mobile phase consisted of acetonitrile-2 mM ammonium acetate (30:70, v/v) containing 0.4% formic acid. The quantification for venetoclax and venetoclax-d8 were m/z 868.1 → 636.1, m/z 876.1 → 644.1, respectively. The linear range was 10–2,000 ng mL−1 for venetoclax. The matrix in normal plasma, hemolytic or lipemic plasma had no significant effect on the detection results. The specificity, recovery and stability also met the acceptance criteria of guiding principles for the validation of biological sample quantitative analysis presented in the Chinese Pharmacopoeia (2015). As a result, this method is particularly suitable for determining venetoclax in hemolytic or lipemic samples from children with acute myeloid leukemia. The method, with the application of monitoring drug concentrations in pediatric patients, was successful.

Open access

Abstract

Due to the relative independence from the operational parameters, the linear retention indices (LRIs) are useful tool in gas chromatography-mass spectrometry (GC-MS) qualitative analysis. The aim of the current study was to develop a multiple linear regression (MLR) model for the prediction of LRIs as a function of selected molecular descriptors. Liquid injection GC-MS was used for the analysis of Essential oils (Rose, Lavender and Peppermint) separating the ingredients by a semi-standard non-polar stationary phase. As a result, a sum of 103 compounds were identified and their experimental LRIs were derived relying on reference measurements of a standard mixture of n-alkanes (from C8 to C20). As a next step, a set of molecular descriptors was generated for the distinguished chemical structures. Further, a stepwise MLR was applied for the selection of the significant descriptors (variables) which can be used to predict the LRIs. From an exploit set of over 2000 molecular descriptors, it was found that only 16 can be regarded as significant and independent variables. At this point split validation was applied: the identified compounds were randomly divided into training (85%) and validation (15%) sets. The training set (87 compounds) was used to derive two MLR models by applying i) the ‘enter’ algorithm (R 2 = 0.9960, RMSЕ = 17) and ii) the ‘stepwise’ one (R 2 = 0.9958, RMSЕ = 17). The predictive power was assessed by the validation set (16 compounds) as follows i) q2 F1 = 0.9896, RMSE = 25 and ii) q2 F1 = 0.9886, RMSE = 26, respectively. The adequateness of both regression approaches was further evaluated. Newly developed headspace-solid phase microextraction (HS-SPME) procedures in combination with GC-MS were used for an alternative analysis of the studied Essential oils. Twelve additional compounds, not previously detected by the liquid sample introduction mode of analysis, were identified for which the values of the significant descriptors were within the working range of the developed MLRs. For the last compounds, the LRIs were calculated and the experimental data was used as an external set for assessment of the regression models. The predictive power for both regression approaches was assessed as follows: Enter RMSE = 41, q2 F2 = 0.9503 and Stepwise RMSE = 40, q2 F2 = 0.9521.

Open access

Abstract

Monitoring benzoylphenylureas (BPUs) residues in ready-to-eat vegetables is of great interest for an adequate assessment of human pesticide exposure. A rapid, inexpensive, simple, and effective method for determining 8 BPUs insecticides in tomatoes and cucumbers was developed and validated. Vortex-assisted liquid-liquid extraction (VA-LLE) followed by dispersive solid-phase extraction (d-SPE) using graphitized carbon black (GCB) for cleanup was used before LC-MS/MS analysis. Different parameters were optimized, including the type and volume of extractants, vortex time, and the type and amount of adsorbents used for cleanup. The evaluation showed that the method has excellent linearity (R 2 ≥ 0.994). The recovered 8 BPUs insecticides from spiked tomato and cucumber samples at 0.01, 0.05, and 0.25 mg kg−1 ranged from 83.2 to 105.2%, with RSD of 4.9–14.6%. The limits of quantitation (LOQs) were 0.0025 mg kg−1 (0.005 mg kg−1 for lufenuron). Within-day repeatability ranged from 3.9 to 13.9%, while between-day repeatability ranged from 8.9% to 17.7%. The optimized method was used to analyze 100 samples of tomatoes and cucumbers marketed in Saudi Arabia.

Open access

A hazai genetikai talajosztályozás megújításának szükségessége - 1.

A nevezéktan és a struktúra korrekcióra szoruló elemeinek azonosítása

The necessity of the renewal of the Hungarian genetic soil classification system - 1.

Identification of the elements of the nomenclature and structure to be corrected
Agrokémia és Talajtan
Authors:
Tibor József Novák
,
Tibor Tóth
,
András Makó
,
Mihály Kocsis
,
Zsófia Bakacsi
,
András Bidló
,
Károly Bartha
,
Szabolcs Czigány
,
Gergely Tóth
,
Adrienn Horváth
, and
Hilda Hernádi

A tanulmány a magyar genetikai osztályozás sok szempontból kritizált rendszerének következetlenségeit, illetve ellentmondásait elemzi azzal a szándékkal, hogy a rendszer fő jellemzőinek: a talajtaxonok elnevezésének és tartalmának megőrzése mellett szakmai párbeszédet indítson a hibák kijavításának lehetőségéről és a rendszer megújításáról.

Rámutattunk a nevében és koncepciójában genetikus, szerkezetében hierarchikus osztályozási rendszer hibrid jellegére: arra, hogy a fő genetikus szempont csak a főtípusok aggregációs szintjén érvényesül maradéktalanul, míg a típusoknál már mintegy egyharmad arányban diagnosztikus szempontok jelentik az elkülönítés alapját. Alsóbb hierarchiaszinteken (altípus, változat) pedig csaknem tisztán diagnosztikus az osztályozás. Listába rendeztük azokat a problémás típus, altípus és változati elnevezéseket, amelyek több hierarchiaszinten azonos névvel, és esetleg eltérő tartalommal fordulnak elő, illetve azonos hierarchiaszinten, de eltérő definíciókkal szerepelnek, vagy éppen szinonímnak tekinthetők, az eltérő elnevezés mögött rejlő azonos tartalom miatt. A vitacikk szándéka, hogy a kiszűrt hibák, következetlenségek széleskörű szakmai egyeztetést követően javításra kerüljenek.

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