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81.
Fuad A. Ababneh Idrees F. Al-Momani 《International journal of environmental analytical chemistry》2013,93(7):755-766
During 2010, the concentrations of mercury and eight other trace elements in 90 canned tuna samples commercialised in Jordan were determined using mercury analyser (Hydra C®) and the inductively coupled plasma-optical emission spectrometer (ICP-OES). The mean concentrations and ranges for elements analysed in mg?kg ? 1 (wet base) were as follows: total Hg (0.21; 0.06–0.57), Cd (0.06;?<?0.01–0.63), Pb (0.09; <0.04–0.24), total As (0.74; 0.11–1.56), Ni (0.51; 0.03–2.85), V (0.04; <0.03–0.1), Al (0.26; 0.08–1.63), Ba (0.13; 0.05–0.42) and Ag was not detected in any of the analysed samples (<0.02?mg?kg?1). The data obtained in the present study compared well with data obtained from similar studies carried out in different parts of the world. Few samples had the mercury and cadmium levels slightly exceeding the Codex Committee on Food Additives and Contaminants draft guidelines. However, the estimated weekly intakes of these metals showed that there was no health risk associated with the consumption of the analysed canned tuna samples. 相似文献
82.
Vijay V. Dabholkar Faisal Y. Ansari 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):298-305
Ultrasound accelerated synthesis of 2,3-(substituted)benzo-1,4-thiazino[5,6-b]-4H-9H-7- methyl-10-oxoquinolines (4), 7-substituted-2,2-dimethyl-2,3-dihydro-1H,10H-phenothiazin- 4-one (5), 4-substituted-3,9, 10-trihydro-11-oxo-quinolino[2,3-b]-1,3,4-thiadiazino[2,3-d]- 1,2,4-triazole (6), and 7,7-dimethyl-7,8-dihydro-3H,5H,6H-1,2,4-triazolo[3,4-b][1,3,4] benzothiadiazin-9-one (7) from carbostyril and dimedone using sulfur powder and iodine as a catalyst in THF is reported. The structures of the compounds have been elucidated on the basis of spectral and elemental analysis. 相似文献
83.
Mohammed M. Rahman Aslam Jamal Sher Bahadar Khan Mohd Faisal 《Journal of nanoparticle research》2011,13(9):3789-3799
The production of low-dimensional nanoparticles (NPs) with appropriate surface modification has attracted increasing attention
in biological, biochemical, and environmental applications including chemical sensing, photocatalytic degradation, separation,
and purification of toxic molecules from the matrices. In this study, iron oxide NPs have been prepared by hydrothermal method
using ferric chloride and urea in aqueous medium under alkaline condition (pH 9 ~ 10). As-grown low-dimensional NPs have been
characterized by UV–vis spectroscopy, FT-IR, X-ray diffraction, Field emission scanning electron microscopy, Raman spectroscopy,
High-resolution Transmission electron microscopy, and Electron Diffraction System. The uniformity of the NPs size was measured
by the scanning electron microscopy, while the single phase of the nanocrystalline β-Fe2O3 was characterized using powder X-ray diffraction technique. As-grown NPs were extensively applied for the photocatalytic
degradation of acridine orange (AO) and electrochemical sensing of ammonia in liquid phase. Almost 50% photo-catalytic degradation
with AO was observed in the presence of UV sources (250 W) with NPs. β-Fe2O3 NP-coated gold electrodes (GE, surface area 0.0216 cm2) have enhanced ammonia-sensing performances in their electrical response (I–V characterization) for detecting ammonia in liquid phase. The performances of chemical sensor were investigated, and the results
exhibited that the sensitivity, stability, and reproducibility of the sensor improved significantly using β-Fe2O3 NPs on GE surface. The sensitivity was approximately 0.5305 ± 0.02 μAcm−2mM−1, with a detection limit of 21.8 ± 0.1 μM, based on a signal/noise ratio of 3 with short response time. 相似文献
84.
Vladimir V. Egorov Andrei D. Novakovskii Faisal A. Salih Andrei V. Semenov Yauhen B. Akayeu 《Electroanalysis》2020,32(4):674-682
The recently proposed interface equilibria‐triggered dynamic diffusion model of the boundary potential has proven its high predictive efficiency for quantification of the ion exchange and co‐extraction effects at the interface, as well as of the trans‐membrane transfer effect, on the electrode response. It is applicable for both ion exchanger‐based and neutral carrier‐based electrodes. In this communication, the adaptability of this model to more complex cases, when non‐ion‐exchange extraction processes at the interface (partition of organic acids’ and bases’ molecular forms and extraction of ionic associates) are coupled with protolytic equilibria in the aqueous phase and with self‐solvation process in the membrane phase, is demonstrated. By the example of electrodes reversible to ions of highly lipophilic physiologically active bases and acids (amiodarone, verapamil, vinpocetine, salicylic acid), it is shown that the peculiarities of their functioning, such as a very strong pH effect on the potential of cation‐selective electrodes, non‐monotonic pH dependence of the potential and super‐Nernstian response slope in certain pH region for a salicylate‐selective electrode, are well described within the model. 相似文献
85.
A procedure for extraction of the rate-equation parameters of semiconductor laser diodes is presented. Using small signal measurements, we have formulated a complete set of equations, which can be resolved analytically to obtain a solution for a combination of parameters that constitute a modified rate-equation model and is presented here for the first time. The proposed method does not necessitate at, or below threshold measurements, which require high sensitivity from the measuring equipment. Furthermore, without the need for any optimization, the solution to the rate equations is completely self-consistent since the parameters are linked together through functional relationships. With this new method, the determination of all the necessary rate-equation parameters to carry out large signal simulation is exclusive of the measurements for signal chirp, and as such computation of the chirp parameter is not included here. Comparison between large signal measurements and simulations from the computed parameters show very good agreement for a range of above threshold bias currents. 相似文献
86.
The long-term performance of a submerged membrane fungi reactor was observed while a synthetic textile wastewater containing either or both of the two structurally different azo dyes was continuously fed. Compared to the Acid Orange II dye (simpler structure), higher biosorption but slower biodegradation of the polymeric dye (Poly S119) was observed in sterile batch tests. In the membrane bioreactor (MBR), although a relative abundance of fungi (66%) without any specific control of bacterial contamination could be maintained, unlike in pure fungus culture, enzymatic activity was below detection limit. Nevertheless, >99% removal of Poly S119 was consistently achieved under a dye loading of 0.1 g L−1 d−1 (HRT = 1 d). Comparison of the reactor-supernatant (SQ) and the membrane-permeate (PQ) qualities (31% improvement) revealed the significant contribution of the membrane to the overall removal (biosorption, cake layer filtration, biodegradation) of Poly S119. Contrary to the faster removal of Orange II in batch test, membrane-permeate quality revealed 93% removal of the dye in MBR (corresponding SQ = 82%). However, excellent (>99%) stable removal of Orange II or of both the dyes together, as well as stable enzymatic activity was observed following addition of powdered activated carbon (PAC) in the MBR. In accordance with real textile wastewater, dye contributed only 5% of the TOC loading (0.944 g L−1 d−1) in this study. In contrast to low TOC removal by fungi alone, the MBR containing mixed microbial community steadily achieved >98% removal, which improved further to >99% after PAC addition. 相似文献
87.
Mohd Nazam Ansari Najeeb Ur Rehman Aman Karim Faisal Imam Abubaker M. Hamad 《Molecules (Basel, Switzerland)》2021,26(5)
The purpose of the research was to examine the protective effect of essential oil from Thymus serrulatus Hochst. ex Benth. (TSA oil) against cadmium (Cd)-induced renal toxicity. The experimental protocol was designed using 30 healthy adult Wistar albino rats allocated into five groups containing six animals in each group. Group 1 was treated as normal control and groups 2, 3, 4, and 5 were treated with cadmium chloride (CdCl2, 3 mg/kg, IP) for 7 days. Group 3 was also treated with silymarin (100 mg/kg, PO) as a standard group, while groups 4 and 5 were administered with TSA oil at doses of 100 and 200 mg/kg PO, respectively. The nephrotoxicity was measured with various parameters such as kidney function markers, oxidative stress markers (glutathione (GSH) and malondialdehyde (MDA)), and messenger ribonucleic acid (mRNA) expression levels of inflammatory factors. The histological studies were also evaluated in the experimental protocol. The CdCl2-treated groups showed a significant increase in the levels of serum kidney function markers along with MDA levels in kidney homogenate. However, renal GSH level was found to be reduced significantly. It was found that CdCl2 significantly upregulated the nuclear factor levels of kappaB (NF-κB p65), inducible nitric oxide synthase (iNOS), and small mothers against decapentaplegic (Smad2) as compared to the normal control group. On the other hand, TSA oil significantly improved the increased levels of serum kidney function markers, non-enzymatic antioxidants, and lipid peroxidation. In addition, TSA oil significantly downregulated the increased expression of NF-κB p65, iNOS, and Smad2 in Cd-intoxicated rats. Moreover, the histological changes in the tissue samples of the kidney of Cd-treated groups were significantly ameliorated in the silymarin- and TSA-oil-treated groups. The present study reveals that TSA oil ameliorates Cd-induced renal injury, and it is also proposed that the observed nephroprotective effect could be due to the antioxidant potential of TSA oil and healing due to its anti-inflammatory action. 相似文献
88.
Faisal Omar Abu Montakim Tareq Ali M. Alqahtani Kuldeep Dhama Mohammed Abu Sayeed Talha Bin Emran Jesus Simal-Gandara 《Molecules (Basel, Switzerland)》2021,26(8)
Plant-based indole alkaloids are very rich in pharmacological activities, and the indole nucleus is considered to contribute greatly to these activities. This review’s fundamental objective is to summarize the pharmacological potential of indole alkaloids that have been derived from plants and provide a detailed evaluation of their established pharmacological activities, which may contribute to identifying new lead compounds. The study was performed by searching various scientific databases, including Springer, Elsevier, ACS Publications, Taylor and Francis, Thieme, Wiley Online Library, ProQuest, MDPI, and online scientific books. A total of 100 indole compounds were identified and reviewed. The most active compounds possessed a variety of pharmacological activities, including anticancer, antibacterial, antiviral, antimalarial, antifungal, anti-inflammatory, antidepressant, analgesic, hypotensive, anticholinesterase, antiplatelet, antidiarrheal, spasmolytic, antileishmanial, lipid-lowering, antimycobacterial, and antidiabetic activities. Although some compounds have potent activity, some only have mild-to-moderate activity. The pharmacokinetic profiles of some of the identified compounds, such as brucine, mitragynine, 7-hydroxymitragynine, vindoline, and harmane, were also reviewed. Most of these compounds showed promising pharmacological activity. An in-depth pharmacological evaluation of these compounds should be performed to determine whether any of these indoles may serve as new leads. 相似文献
89.
Two ruthenium(II) dithiocarbamates, cis-[Ru(DMP)2L](BF4), where L = 4-(4-methoxy-phenyl)piperazine-1-carbodithioate (1) and 4-(3-methoxyphenyl)piperazine-1-carbodithioate (2) and DMP = 2,9-dimethyl-1,10-phenanthroline, have been synthesized and characterized. The DNA-binding affinity of these metal complexes was investigated by UV–visible spectrophotometry with DNA-binding constants of 6.2 × 104 M?1 (1) and 1.2 × 105 M?1 (2) and electrostatic binding mode was confirmed by viscometric measurements. For insight into the structural differences, both complexes were studied computationally. B3LYP/LANL2DZ level of Density Functional Theory was used for the computational studies in Gaussian 09. The optimized bond lengths are in agreement with the reported values. Comparative computational studies reveal interesting transformations in bond lengths, angles, Natural Bond Orbital charges, molecular orbitals, Molecular Electro Static Potentials, and global chemical reactivity indices. Based on quantum chemical results a structure–activity relationship has been attempted. 相似文献
90.
Naveed Akhtar Shad Muhammad Munir Sajid Yasir Javed Nasir Amin Muhammad Ikram Kanwal Akhtar Gulzar Ahmad Faisal Ali Aamir Razaq 《中国化学会会志》2020,67(6):1045-1053
Zinc oxide (ZnO) nanostructures were synthesized via a one-step solid-state reaction approach in ammonia (NH3) gas environment with different temperature ramp rates. The so-formed nanostructures were characterized using X-ray diffraction (XRD) for phase identification, where the typical wurtzite hexagonal structure was observed. Scanning electron microscopy (SEM) confirmed the particle size to be in the range 45–50 nm, the same as calculated by the XRD pattern for the ramp rate of 10 °C/min. Energy dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed the chemical purity of the samples. The photoluminescence (PL) spectrum indicated multiple near-band-edge emissions and energy-band emissions. Then, these ZnO nanomaterials were used for the degradation of crystal violet (CV) dye under UV light irradiation. The CV solution was completely degraded in 2 hr. The initial photocatalyst and dye amounts of 0.2 g/100 ml and 0.5 mg/L, respectively, were found to be the optimum values for maximum degradation efficiency. The ZnO-based photocatalyst was stable up to three cycles of reuse. These results indicate that the high surface area and porosity of the nanomaterials are responsible for the high efficiency, which was confirmed by specific surface area analysis. 相似文献