Two new acyl thiourea derivatives (1 and 2) and their Ni(II) and Cu(II) complexes (1a, 1b, 2a and 2b) have been synthesized. These compounds have been characterized by FT-IR, UV–Vis spectra, 1H and ...C13 NMR spectroscopic techniques, and have displayed satisfactory elemental analysis. X-ray crystallographic studies reveal that compound 2a is a cis-complex and crystallizes in monoclinic crystal system, with space group P21/c. The ligands act as bidentate chelators in complexes and coordinated to the central atom through O and S atoms. Moreover, cytotoxic, antibacterial and antifungal activities of compounds have been assayed against Brine shrimp eggs, three Gram negative strains including Enterobacter aerogenes, Bordetella bronchiseptica and Salmonella typhimurium and three fungal strains such as Aspergillus fumigatus, Fusariumsolani and Mucor specie, respectively. Compound 2 has displayed good activity.
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•Two new acyl thiourea derivatives and their metal complexes have been synthesized.•The compounds have been characterized spectroscopically.•Single crystal X-ray diffraction studies suggest four coordinated geometry for complex 2a.•Compound 1a displays strong antifungal activity.
Fault detection based on external leakage flux can address various faults, such as short circuit faults in stators and rotors. External leakage flux sensing technology, as a noninvasive method, has ...been attracting increasing attention and research. However, for a high-power doubly fed induction generator (DFIG), the external leakage flux signals of the generator are easily overwhelmed by a strong noise background, and the fault diagnosis and recognition of stator and rotor interturn short circuits is complicated, which limits the practical engineering application of leakage flux sensing technology. Aiming at addressing interturn short circuit faults in DFIGs, this paper proposes a method for fault feature extraction and recognition of stator and rotor short circuits based on variational mode decomposition (VMD) and the refined composite multiscale dispersion entropy (RCMDE) analytical method for the external flux leakage of the generator. The optimized parameters of VMD are selected automatically by the genetic algorithm (GA), and VMD is adopted to adaptively decompose the external leakage flux signals into a series of intrinsic mode function (IMF) components. The evaluation criterion based on the correlation number in the frequency domain combined with the autocorrelation function is used to select the best IMF components with clear features. Two different components are chosen to reconstruct the flux leakage signal. The characteristic frequency of the reconstructed signal is analyzed by the Hilbert-Huang transform (HHT) and the total harmonic effective value of the characteristic component. To effectively identify and diagnose the generator stator and rotor interturn short circuit fault, RCMDE is used for the flux leakage reconstructed signal. The experimental results under different stator and rotor short-circuit levels show that this diagnosis method can effectively extract the weak feature information from the external flux leakage signals and perform fault feature extraction and recognition for stator and rotor short circuits.
The hunting frequency is an inherent characteristic parameter of the wheel-rail system and is able to affect the modal behavior of the vehicle system due to its continuous variation with running ...speeds, which in turn dominates some structural resonance related-dynamics. This study focuses on the variation mechanism of the hunting frequency and its effect on carbody hunting stability, starting from a single wheelset to a flexible bogie, then to the entire vehicle system with both primary and secondary suspensions. The minimal modal distance-based tracking method is proposed to continuously trace the hunting frequency and other concerned modal parameters. The variables in the wheel-rail contact system and suspension system are controlled individually to study their effects on hunting frequency variation under the speed parametric excitation. The saturation mechanism of hunting frequency is revealed by limit thought and the limit value is analytically expressed. The root loci curves are separated and recognized by utilizing the modal tracking method and normalized amplitudes distribution related to the modal shape and kinetic energy. From the perspectives of the modal frequency, damping ratio and modal shape, the modal behavior features at or around the frequency coupling speed (the speed at which the hunting frequency equals carbody rigid modal frequencies) are analyzed and summarized. Based on the joint parametric excitation of the speed and equivalent conicity, the frequency coupling speed is believed as the primary factor to dominate the carbody hunting stability by affecting the minimal damping ratio. In addition to the modal frequency, the natural damping ratio of carbody rigid modes can also affect the minimal damping ratio related to frequency coupling speed. The investigation enriches the understanding of hunting motion and provides assistance for the stability design of modern railway vehicles by considering the variation mechanism of hunting frequency.
Iron is one of the most important micronutrients for crop plants due to its use in important physiological processes such as photosynthesis, mitochondrial respiration, metal homeostasis, and ...chlorophyll synthesis. Crop plants have adapted different strategies for uptake, transport, accumulation, and storage of iron in tissues and organs which later can be consumed by humans. Estimates indicate that about 2 billion people (33% of human population) are at risk of iron deficiency in which infants, children, and pregnant women are potentially compromised. Biofortification refers to the increase in concentration of micronutrients in edible parts of plants and understanding the pathways for iron accumulation in plants is necessary for breeding iron‐enriched crops. Iron‐biofortified crops are also one of the key factors in achieving multiple United Nations Sustainable Development goals. This review article covers different strategies of iron acquisition and transport in plants, its bioavailability, coping with the iron deficiency as a global perspective, the current status of iron biofortification, and how breeding future biofortified crops could be helpful in combating the said issue in a sustainable manner.
Melanoma is considered the most serious type of skin cancer. All over the world, the mortality rate is much high for melanoma in contrast with other cancer. There are various computer-aided solutions ...proposed to correctly identify melanoma cancer. However, the difficult visual appearance of the nevus makes it very difficult to design a reliable Computer-Aided Diagnosis (CAD) system for accurate melanoma detection. Existing systems either uses traditional machine learning models and focus on handpicked suitable features or uses deep learning-based methods that use complete images for feature learning. The automatic and most discriminative feature extraction for skin cancer remains an important research problem that can further be used to better deep learning training. Furthermore, the availability of the limited available images also creates a problem for deep learning models. From this line of research, we propose an intelligent Region of Interest (ROI) based system to identify and discriminate melanoma with nevus cancer by using the transfer learning approach. An improved k-mean algorithm is used to extract ROIs from the images. These ROI based approach helps to identify discriminative features as the images containing only melanoma cells are used to train system. We further use a Convolutional Neural Network (CNN) based transfer learning model with data augmentation for ROI images of DermIS and DermQuest datasets. The proposed system gives 97.9% and 97.4% accuracy for DermIS and DermQuest respectively. The proposed ROI based transfer learning approach outperforms existing methods that use complete images for classification.
A flow injection (FI) methodology using the acidic potassium permanganate (KMnO4)–rhodamine‐B (Rh‐B) reaction with chemiluminescence (CL) detection was established to determine acetochlor and ...cartap‐HCl pesticides in freshwater samples. Experimental parameters were optimized, and Chelex‐100 cationic exchanger mini column and solid‐phase extraction (SPE) were used as phase separation techniques. Linear calibration curves were observed for the standard solutions of acetochlor and cartap‐HCl over the ranges 0.005–2.0 mg L−1 y = 1155.8x + 57.551, R2 = 0.9999 (n = 8) and 0.005–1.0 mg L−1 y = 979.76x + 14.491, R2 = 0.9998 (n = 8) with LODs and LOQs of 7.5 × 10−4 and 8.0 × 10−4 mg L−1 (3σ blank) and 2.5 × 10−3 and 2.7 × 10−3 mg L−1 (10σ blank), respectively, with an injection throughput of 140 h−1. These methods were used to estimate acetochlor and cartap‐HCl with or without the SPE procedure, respectively, in spiked freshwater samples. Results obtained were not significantly different at a 95% confidence level to those of other reported methods. Recoveries for acetochlor and cartap‐HCl were obtained over the ranges 93–112% (RSD = 1.9–3.6%) and 98–109% (RSD = 1.7–3.8%), respectively. The most probable CL reaction mechanism was explored.
Flow injection methodology with acidic potassium permanganate and rhodamine‐B chemiluminescence reaction was used to determine acetochlor and cartap‐HCl pesticides in freshwater samples. Linear ranges were observed as 0.005–2.0 mg L−1 with injection throughput of 140 h−1. The methods were used to estimate acetochlor and cartap‐HCl with and without SPE procedure respectively in spiked fresh‐water samples with calculated recoveries of 93–112% and 98–109%, respectively. The most probable CL reaction mechanism was explored.
This paper introduces a novel approach for detecting inter-turn short-circuit faults in rotor windings using wavelet transformation and empirical mode decomposition. A MATLAB/Simulink model is ...developed based on electrical parameters to simulate the inter-turn short circuit by adding a resistor parallel to phase “a” of the rotor. The resulting high current in the new phase indicates the presence of the short circuit. By measuring the rotor and stator three-phase currents, the fault can be detected as the currents exhibit asymmetric behavior. Fluctuations in the electromagnetic torque also occur during the fault. The wavelet transform is applied to the rotor current, revealing an effective analysis of sideband frequency components. Specifically, changes in amplitude and frequency, particularly in d7 and a7, indicate the presence of harmonics generated by the inter-turn short circuit. The simulation results demonstrate the effectiveness of wavelet transformation in analyzing these frequency components. Additionally, this study explores the use of empirical mode decomposition to detect faults in their early stages, observing substantial changes in the instantaneous amplitudes of the first three intrinsic mode functions during fault onset. The proposed technique is straightforward and reliable, making it suitable for application in wind turbines with simple electrical inputs.
Medicinal plants have great importance to the consumer health, as beside beneficial compounds, plants can accumulate essential and nonessential metals from soil and surrounding environments, leading ...to consumer health risks. Assuming this, the present study is aimed at evaluating the elemental composition and daily dose standardization based on essential and nonessential trace element presence in of bark, leaves, and roots of Berberis baluchistanica Ahrendt, a common medicinal plant used as a folk medicine in the region. Atomic absorption and flame emission spectroscopy were performed to analyze the presence of essential and nonessential elements manganese (Mn), copper (Cu), lead (Pb), nickel (Ni), iron (Fe), sodium (Na), and potassium (K). Among the essential elements, K was present at high concentrations in the bark (8926.98±0.32 μg/g), leaves (7922.77±0.42 μg/g), and roots (6668.5±0.96 μg/g) of the plant. The estimated concentration of Na was higher in leaves (1782.56±0.13 μg/g), followed by roots (1089.5±0.71 μg/g) and bark (572.8±0.62 μg/g). The Fe concentration varied in the range of 394.7±0.3 μg/g in bark, 1298.3±0.54 μg/g in leaves, and 1208.9±0.7 μg/g in roots. The trace transition element Mn was highest in leaves (42.7±0.99 μg/g), followed by roots (33.5±0.94 μg/g) and bark (22±1 μg/g). The Cu concentration was low, ranging from 20.1±0.63 to 22.67±0.7 μg/g in leaves, bark, and roots. The obtained concentration of nonessential element Pb was relatively lower than the permissible range (10 mgL–1) established by the World Health Organization. The elemental concentrations in all parts were within the set limits for provisional tolerable daily maximum intake (PTDMI) and provisional tolerable weekly intake (PTWI), and the hazard quotient index (HQ) was below 1 for all toxic metals. The micro and macroelemental distribution and the overall medicinal potential of any medicinal plant can be correlated for dose risk estimation, which will be useful in providing knowledge regarding the contraindication associated with folk medicines. In the present study, based on the elemental composition, it was calculated that the daily safe dose for Berberis baluchistanica is approximately 2-5 g/day of raw powder for an adult, which must not be exceeded to this safe range.
Nanostructures decorated with perfectly ordered porous anodic aluminum oxide templates have attained recent research interest for the production of highly efficient energy storage devices. Anodic ...aluminum oxide porous templates were synthesized using a two-step anodization technique in this work. Pure BiFeO3 and Zr–BiFeO3 nanostructures were grown on these ordered templates by well-controlled fluoride ions assisted autoclave enclosed hydrothermal method. Crystallographic information discloses the presence of rhombohedral crystal structure with geometric space group R3c belongs to BiFeO3. The morphological analysis depicts the formation of an average pore size of approximately 75 nm in anodic aluminum oxide templates. BiFeO3 contains fibrous nanoflakes like morphology with minute content of the monoclinic zirconia phase in Zr–BiFeO3. Optical measurements demonstrate a considerable variation in absorption and bandgap of anodic aluminum oxide with the growth of nanostructures. A significant increase in dielectric permittivity from 17.17 for anodic aluminum oxide to 187.19 for Zr incorporated compositions with a relatively low tangent loss of 0.66.
•Synthesis of ordered anodic aluminum oxide porous templates using two step anodization.•Autoclave enclosed hydrothermal growth of fibrous nano flakes on AAO templates.•Crystallographic and microstructural information reveals the formation of rhombohedral Al2O3.•Optical measurements demonstrate a considerable variation in absorption and band gap of AAO with growth of nanostructures.•A significant increase in dielectric permittivity was observed in Zr containing compositions.
Karnal bunt (KB) is a seed and airborne wheat disease caused by the fungus
Tilletia indica
Mitra. The floret-infecting fungus damages grains and adversely affects wheat quality through the production ...of trimethylamine. Deployment of host-plant resistance is the best strategy to combat this disease. The present study explored two sources of genetic resistance to KB by developing recombinant inbred lines (RILs) with a common susceptible parent. Munal × WL711 and SAUAL/KIRITTI/SAUL × WL711 produced 275 RILs each which were evaluated for KB disease resistance under four environments. The minimum value for disease incidence was 0% while the maximum values were 8.14% and 10.38% during 2018–2019 and 2019–2020, respectively. This study identified several RILs with durable and heritable resistance against KB, while SAUAL/KIRITTI/SAUL was identified as the highest-performance resistant parent. Based on the best linear unbiased estimates across environments, two bulk populations (resistant and susceptible) were developed from each set of progeny and were subjected to genome-wide single nucleotide polymorphism (SNP) genotyping using a 50K Affymetrix SNP array. Bulked segregation analysis showed that the maximum SNP index was identified on chr2A, chr6A, and chr7A in Munal × WL-711 while it was on chr4B and chr7B in the SAUAL/KIRITTI/SAUL × WL711 population. Taken together, the identified RILs might serve as breeding material for the development of KB-resistant wheat cultivars in the future.
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