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1

Studies on Cucumber Production Using Substrate Culture under North Sinai Conditions

Abd El-Baset Ashraf Ali

Journal of Ecological Engineering

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2023

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Vol. 24, nr 6

40--53

EN

A wide range of soilless cultivation techniques have been developed and introduced for intensive cropping systems and for boosting the crop yield of many vegetables, mainly in greenhouses. Adoption of some local natural by-products to be utilized as a substrate growing medium to overcome soil-related problems appeared to be a promising project. Therefore, greenhouse experiments were conducted at the Baloza Experimental Station of the Desert Research Center (DRC), North Sinai Governorate, Egypt, during the two consecutive winter growing seasons of 2016–2017 and 2017–2018. These experiments aimed to investigate the effects of seven growing substrate culture treatments of separated or mixed sand obtained from sand dunes and date palm tree residues (Karenna) on plant vegetative growth, flowering, fruit yield and quality traits, and fruit nutritional values of cucumber plants (Cucumis sativus L.) Filial-1 hybrid 1101. Crop evapotranspiration reference (ETc) and water use efficiency (WUE), as well as treatment feasibility, were also studied. The experiment was set up in a complete randomized block design with three replicates. The obtained results strongly indicated that growing substrate media containing 25% sand (S) from sand dunes mixed with 75% grinded Karenna (Kg) of date palm (1 S + 3 Kg) significantly recorded the superiority of all studied characters of plant vegetative growth, number of flowers, fruit set, yield and its components, as well as fruit N, P and K contents, compared with other growing substrate medium treatments. On the contrary, the worst values of all studied parameters were achieved when sand was used alone (100% S) as a growing media. Furthermore, the highest water use efficiency and net income values were also attained by the 1 S + 3 Kg media treatment relative to the other growing substrate medium treatments.

2

Tillage, Residues Management, and Nitrogen Fertilization Effects on Soil Organic Status, Soil Quality, and Soft Wheat in the Moroccan Semi-Arid

Et-Tayeb Hiba, Ibno Namr Khalid, El Mzouri El Houssine, El Bourhrami Bouchra, Moussadek Rachid

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 2

173--184

EN

Sustainable management of agricultural practices can improve soil organic status, soil quality (SQ), and yields. The study was conducted to test the impact of tillage (conventional (CT) and no-till (NT)), residues (vetch (C1) and uncover soil (C0)), and three nitrogen (N) fertilization rates (30, 60, and 90 N kg ha-1) on soil organic carbon (SOC), total nitrogen (N), C/N ratio, soft wheat yields and SQ. The experiment was established in 2010 in the Moroccan semi-arid. After ten years, the SOC concentration was greater under NT (9.4 g/kg) compared to CT (8.4 g/kg). Crop residues also enhanced SOC (10 g/kg) contrary to C0 (8.1 g/kg). Application of N fertilization showed profound effects on total N, increasing levels of N fertilization led to higher total N irrespective of tillage. Crop residues increased total N (0.6 g/kg) better than C0 plots at the horizon 20–40 cm. Soft wheat revealed an improvement under NT (4213.8 kg ha-1) versus CT (3785.6 kg ha-1) and it responded positively to the N application. For SQ evaluation through the indexing methods (SQI), principal component analysis was done for eight soil indicators to select the minimum data set (MDS), which were subsequently normalized and integrated into the SQI, additive (SQIANL), and weighted (SQIWNLM). NT revealed higher scores (0.52; 0.6) than the CT (0.46; 0.53) for SQIANL and SQIWNL, respectively, at the horizon 0–20 cm. the residues layer on the soil surface improved SQIWNL score (0.59) compared to C0 (0.55). Moreover, the correlation (r) with yield and the sensitivity (S), allowed us to choose SQIWNL, as the best index (highest r and S) to evaluate SQ under different practices studied. Indeed, SQIWNL revealed an intermediate SQ under NT and at C1 treatments, compared to CT and C0 (low SQ).

3

Determination of malathion and its residues by normal-phase high-performance liquid chromatography method

Velkoska-Markovska Lenche, Petanovska-Ilievska Biljana

Acta Chromatographica

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2022

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Vol. 34, no. 3

315--322

EN

The quality of pesticide formulations has an impact on the crop safety, environment and human health. Therefore, the development of new analytical methods for the determination of active substances in pesticide formulations in order to control their quality, as well as, their residues in food samples in order to ensure food safety, is always welcome. A new, simple, precise and accurate normal-phase high-performance liquid chromatography (NP-HPLC) method for determination of an active ingredient malathion in the commercial emulsifiable concentrate pesticide product has been developed and validated. The analysis was carried out on a LiChrosorb CN (250 x 4 mm, 5 μm) analytical column using isocratic elution with mobile phase consisted of n-hexane and dichloromethane (80/20, v/v), flow rate of 1 mL/min, constant column temperature at 25 °C and ultraviolet diode-array detection at 220 nm. The obtained values for multiple correlation coefficients (R2 ≥ 0.9990), relative standard deviation of retention times, peak areas and heights (RSD ≤ 1.14%), recoveries ranged from 98.97 to 101.62%, revealed that the developed method has a satisfactory linearity, precision and accuracy. Also, the developed method was successfully applied for determination of malathion residues in apple juice samples, after preliminary sample preparation using solid-phase extraction. Specificity, selectivity, linearity, matrix effect, precision and accuracy were tested in order to validation of this method. The obtained results were in acceptable ranges and indicated that the developed method is suitable for routine determination of malathion in the pesticide formulation, as well as for determination of malathion residues in apple juice samples. The run time of HPLC analysis was about 6 min.

4

Representative commodity for six leafy vegetables based on the determination of six pesticide residues by gas chromatography

Song Shiming, Huang Huili, Chen Zhaojie, Wei Jie, Deng Cheng, Tan Huihua, Li Xuesheng

Acta Chromatographica

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2019

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Vol. 31, no. 1

49--56

EN

A residue analytical method was developed for the determination of trichlorfon, chlorpyrifos, dimethoate, β cypermethrin, deltamethrin, and chlorothalonilin in six leafy vegetables by gas chromatography–electron capture detector (GC–ECD) and gas chromatography–flame photometric detector (GC–FPD). The method had a good linearity (R2 ≥ 0.9924) and precision (RSD ≤ 14.0%). The limits of quantification (LOQ) of six pesticides were all 0.01 mg/kg. Average recoveries of six pesticides ranged from 81% to 119%. The developed method was successfully applied to study the initial deposits, degrade characteristics, and terminal residues for six pesticides applied to six leafy vegetables under the same dose of formulation. The half-life of six pesticides was in the range of 0.8–8.8 days. The highest initial deposits, maximal residues, and terminal residues were found on leaf mustard and sweet potato leaves as the same pesticides were applied in different crops. Therefore, leaf mustard can be selected as representative commodity in the same subgroup to realize the residual extrapolation. This conclusion should be considered as a complement on crop classification of China.

5

Development and validation of a rapid HPLC method for multiresidue determination of erythromycin, clarithromycin, and azithromycin in aquaculture fish muscles

Habibi B., Ghorbel-Abid I., Lahsini R., Ben Hassen D. Chehimi, Trabelsi-Ayadi M.

Acta Chromatographica

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2019

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Vol. 31, no. 2

109--112

EN

An accurate, sensitive, and reproducible high-performance liquid chromatographic method with diode array detection has been developed for simultaneous determination of erythromycin, clarithromycin, and azithromycin residues in fish muscles. Analysis was carried out using a Shodex Asahipak high-performance liquid chromatography (HPLC) column, monitoring was at 210 nm and a mobile phase consisting of a mixture of acetonitrile and phosphate buffer (pH 11 ± 0.05) in the ratio of 60:40 (v/v). Solid-phase extraction method was used in samples extraction and purification. Recoveries were in the range 72.0–92.2% with relative standard deviation (RSD) from 2.3% to 8.3%. This method was validated for fish muscles in aquaculture following the commission decision 2002/657/EC criteria. It is demonstrated that the new method is robust for detection and quantification of the three macrolides residues. Decision limit (CCα) was from 214 to 228 μg/kg and capacity of detection (CCβ) was from 228 to 256 μg/kg.

6

Problems of designing state feedback controllers for objects with transfer function zeros

Drozdov V., Abdullin A., Mamatov A.

Power Electronics and Drives

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2017

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Vol. 2 (37), No. 2

77--92

EN

The analysis of the influence of transfer function zeros on the parameters of state feedback controllers has been conducted. If a transfer function of a control object has zeros which are located closely to poles, the control object tends to singularity, and the influence of the input control signal to the states of the control object becomes weaker. The problem of the state feedback controller synthesis becomes ill-conditioned, which leads to the appearance of extremely large state feedback coefficients. In this case, the state feedback coefficients are sensitive to the parameters of the control object. As a result, the parametric robustness of the control system is reduced. Known methods of structural analysis of control object models are included amongst different methods of the numerical evaluation of the controllability and the observability, as well as methods of the model order reduction. These methods have some disadvantages, such as dependence on the state space representation form of the control object, ignoring a part of the control object model. In this paper, some ways of the preliminary structural analysis of the state space models of control objects have been proposed. The singular (Hankel) matrix is proposed for analyzing the properties of control object models. The singular matrix is the invariant characteristic of the control object in various state space forms and it characterizes the property of the control object completeness. As a result of the research, it was found that the coefficients of the state feedback controller are inversely proportional to the determinant of the singular matrix, and the determinant of the singular matrix is equal to the resultant of the transfer function polynomials. Thus the value of the determinant of the singular matrix depends on the location of the zeros of the transfer function. The method of the structural transformation (decomposition) of the control object for the defining the need of the reducing the order of the control object model is proposed.

7

Application of vitrification method for the disposal of municipal sewage sludge

Borowski G.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 1

575--583

PL

W publikacji przedstawiono wyniki badań dotyczące utylizacji odpadów z wykorzystaniem metody zeszklenia. Badana mieszanka odpadów składała się z dosuszonych i rozdrobnionych komunalnych osadów ściekowych w udziale masowym ok. 42%, a pozostałą część stanowiły popioły lotne ze spalania węgla, rozdrobniona stłuczka szkła oraz cement jako spoiwo. Mieszankę aglomerowano w stemplowej prasie hydraulicznej uzyskując brykiety o walcowym kształcie, które następnie nagrzewano w piecu komorowym oraz schłodzono w wodzie. Uzyskane zeszklone wyroby poddano testom badawczym wytrzymałości mechanicznej, mrozoodporności, nasiąkliwości oraz wymywalności związków metali ciężkich. Ich wytrzymałość była wystarczająca pod względem spełnienia wymagań stawianych materiałom przeznaczonym na podbudowy utwardzonych nawierzchni drogowych. Wyniki pomiarów mrozoodporności i nasiąkliwości potwierdziły dobrą odporność na zmienne warunki atmosferyczne. Nie stwierdzono zagrożenia migracji substancji niebezpiecznych zawartych w odpadach oraz wypłukiwania metali ciężkich do środowiska. Zastosowanie zeszklenia brykietów zawierających osady ściekowe umożliwiło zatem uzyskanie produktów bezpiecznych dla środowiska, które mogą być stosowane jako materiał budowlany.

8

Production costs and residues evaluation of Crambe abyssinica as an energy feedstock

Stolarski M., Krzyżaniak M., Śnieg M., Christou M., Alexopoulou E.

Environmental Biotechnology

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2013

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Vol. 9, No. 2

59--64

EN

In Europe, like in other parts of the world, plant species predisposed for use as energy crops are searched for. Among the oil plants grown in European countries, rape is most important although rape oil is mainly a food product. On the other hand, Crambe abyssinica is an oil plant species which is not used to make human food or animal feeds. Besides, Crambe abyssinica oil has a high content of erucic acid, hence it has the potential to be processed into many different products in the power generation or chemical industries. This paper documents results of a field experiment conducted in north-eastern Poland, at the Experimental Station of the University of Warmia and Mazury in Olsztyn, located in Łężany (53°35’ N, 20°36’ E). The aim of this experiment was to determine costs of production of Crambe abyssinica grown in two variants (with and without herbicides). In addition, the quality of by-products (straw and cake) as energy feedstocks was evaluated. Costs of production of Crambe abyssinica seeds in the variant with herbicides were nearly 140€•ha-1 higher than in the variant without herbicides. The yield of pure seeds was by over 110kg•ha-1 higher in the herbicide-treated variant than in the treatment without weed control. However, the yield of straw was higher on fields without application of herbicides, but that straw had a higher moisture content due to the presence of weeds. The lower heating value of crambe straw was 15.3MJ•kg-1 on average and the straw content of ash was 5.68% D.M. The cake obtained from the crop had a much higher lower heating value (21.95MJ•kg-1) and ash content 6.41% D.M. Moreover, it was found to contain much more carbon and hydrogen, as well as five-fold more sulfur than straw.

9

Pozostałości herbicydów w płodach rolnych i glebie

Grygiel K., Sadowski J., Snopczyński T., Wysocki A.

Journal of Ecology and Health

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2012

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R. 16, nr 4

159-163

PL

Herbicydy są obecnie powszechnie stosowane w produkcji roślinnej. Stwarza to ryzyko obecności pozostałości substancji aktywnych między innymi w glebie i płodach rolnych. Substancje aktywne zalegające w glebie mogą powodować uszkodzenia wrażliwych roślin następczych lub zostać wymyte do wód gruntowych. Pozostałości obecne w plonie mogą wywierać niekorzystny efekt na zdrowie konsumentów. Pomimo, że w Polsce notowane są przypadki wykrywania pozostałości herbicydów w płodach rolnych to w zdecydowanej większości przypadków nie przekraczają one dopuszczalnych wartości. Niemniej jednak niezbędny jest stały i regularny monitoring prowadzony zgodnie ze standardami unijnymi.

EN

Currently, herbicides are widely used in plant production. This leads to the risk of the occurrence of the active ingredients in the residues in the soil and in agricultural products. The presence of the active ingredients in the soil can cause damage to sensitive successive crops or may leach into groundwater. Residues in crops may have a detrimental effect on the health of consumers. Although in Poland there are cases of tracing the residuals of herbicides in agricultural products, in the great majority of cases, they do not exceed the acceptable values. However, constant monitoring of herbicide residuals is necessary, should be performed regularly and should meet EU standards.

10

Simultaneous determination of sulf amethazine and sulfadimethoxine in meat, milk and egg by liquid-liquid. Extraction and micellar liquid chromatography

Szymański A.

Chemia i Inżynieria Ekologiczna

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2004

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Vol. 11, nr 11

1259-1265

EN

The method of high-pressure liquid chromatography with micellar mobile phase has been applied for simultaneous determination of sulfamethazine and sulfadimethoxine in food products of animal origin. Preliminary extraction and concentration of analyte have prepared samples for analyses by the liquid-liquid extraction. The linear range of the calibration curves for sulfamethazine and sulfadimethoxine was determined as from 50 to 500 [mu]g/kg (dm3) of the concentrations of the products analysed. The detection limit of both sulfonamides was 25 [mu]g per 1 kg of meat and eggs (1 dm3 milk). The method proposed is characterised by good precision and accuracy. The accuracy of measurements in meat was 3.0 to 12.8%, in milk 2.0 to 4.0%, in eggs 2.0 to 3.3%. The precision did not exceed 6.0% for meat, 4.1% for milk and 5.7% for eggs. The recovery of sulfonamides introduced into the food products studied was determined to vary in the range 87.2% for sulfadimethoxine to 104% for sulfadimethoxine in milk.

PL

Technikę wysokociśnieniowej chromatografii cieczowej z micelarną fazą ruchomą wykorzystano do jednoczesnego oznaczania sulfametazyny i sulfadimetoksyny w środkach spożywczych pochodzenia zwierzęcego. Próbki do analizy przygotowywano, wykorzystując metodę wstępnego wydzielania i zatężania analitu za pomocą ekstrakcji ciecz-ciecz. Zbadano prostoliniowy przebieg krzywych wzorcowych dla sulfametazyny i sulfadimetoksyny w przedziale stężeń od 50 do 500 [mu]g/kg (dm3) analizowanych produktów. Limit detekcji dla obu sulfonamidów wynosił 25 [mu]g na 1 kg mięsa i jaj (l dm3 mleka). Proponowana metoda charakteryzuje się dobrą precyzją i dokładnością. Dokładność dla badanych leków w mięsie przyjmowała wartości od -3.0 do 12.8%, w mleku od -2.0 do 4.0%, natomiast dla jaj wynosiła od -2.0 do 3.3%. Precyzja nie przekraczała 6.0% dla mięsa oraz 4.1% i 5.7% odpowiednio dla mleka i jaj. Wyznaczono również odzysk sulfonamidów wprowadzonych do badanych środków spożywczych. Mieścił się on w przedziale od 87.2% dla sulfadimetoksyny w mięsie do 104% dla sulfadimetoksyny w mleku.

11

Micellar liquid chromatography for the determination of sulfonamide residues in milk and eggs

Szymański A.

Chemia Analityczna

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2003

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Vol. 48, No. 3

429-438

EN

The micellar liquid chromatography for the determination of sulfonamide residues in milk and eggs was coupled with different methods of the sample pre-treatment: direct injection and extractive condensation of the analyte in the solid-solid and liquid-liquid system. The detection limit for the concentration range studied was 0.10 ug mL(-1) (direct sample injection DSJ), 0.05 ug ml/1 (solid-phase extraction SPE), and 0.025 ug ml/1 (liquid-liquid extraction LLE), for milk, and 0.025 ug mL(-1) (SPE and LLE) for eggs. The method provided high precision and accuracy. RSD value did not exceed 8% for milk and eggs, and the accuracy defined as the percentage difference between the mean amount found and that added varied from -2.0 to 5.0. The recovery of the spiked sulfonamides from milk and eggs was in the range from 96% to 105%.

PL

Przeprowadzono badania nad zastosowaniem micelarnej chromatografii cieczowej do oznaczania pozostałości sulfonamidów w mleku i jajach wykorzystując różne sposoby przygotowania próbki do analizy: bezpośredni nastrzyk próbki, ekstrakcyjne zatężenie analitu w układzie ciecz-ciało stałe i w układzie ciecz-ciecz. Granica detekcji w badanym zakresie stężeń w mleku wynosi 0.10 ug ml/1 dla DSI, 0.05 ug ml/1 dla SPE i 0.025 ug ml/(-1) dla LLE oraz w jajach 0.025 ug mL(-1) dla SPE i LLE. Opracowana metoda charakteryzuje się wysoką dokładnością i precyzją; wartość RSD nie przekracza 8% dla mleka i jaj, a dokładność określona jako procentowa różnica pomiędzy wielkością znalezioną, a dodaną do próbki, zmienia się od-2 do 5. Odzysk sulfonamidów wprowadzonych do mleka i jaj mieścił się w przedziale od 96 do 105%.