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51.
Taysir Abdelrhman Musa Mohd Marsin Sanagi Wan Aini Wan Ibrahim Farediah Ahmad Hassan Y. Aboul-Enein 《Food Analytical Methods》2014,7(4):893-901
A method has been developed for the determination of 4-allyl resorcinol and chavibetol from Piper betle leaves using subcritical water extraction combined with high-performance liquid chromatography. Several important parameters, such as effect of extraction temperature, solvent, particle size, flow rate and duration time of extraction were comprehensively optimized. The method showed good linearity in the range of 0.2–30 μg/mL, good correlation coefficients 0.9999 for all studies, acceptable reproducibility (RSD 0.16-5.43, n?=?3), low limit of detection (0.1 μg/mL), satisfactory average recoveries of (92.22 to 111.05 %) from subcritical extraction with water with RSDs of 0.31 to 7.96 %whereas, the average recoveries from subcritical extraction with methanol–water ranged from (96.58 to 110.72) with RSDs of 0.79 to 8.09 %. The method exhibit high extraction yield in range of (1.51 to 34.64 % w/w) obtained from subcritical extraction with water whereas for subcritical extraction with methanol–water the yield obtained in range of (2.08 to 9.06 % w/w). It was found that subcritical extraction with water offered improved extraction efficiency in extraction of the target compounds compared to subcritical extraction with methanol–water. 相似文献
52.
Sachin D. Nerkar;Shakeelur Raheman AR;Mohammed K. Al Mesfer;Khursheed B. Ansari;Mohd Shariq Khan;Amol B. Deore;R. R. Attarde; 《Microscopy research and technique》2024,87(10):2475-2486
Field emission finds a vital space in numerous scientific and technological applications, including high-resolution imaging at micro- and nano-scales, conducting high-energy physics experiments, molecule ionization in spectroscopy, and electronic uses. A continuous effort exists to develop new materials for enhanced field emission applications. In the present work, two-dimensional (2D) well-aligned CdSSe flake flowers (CdSSe-FFs) were successfully grown on gold-coated silicon substrate utilizing a simple and affordable chemical bath deposition approach at ambient temperature. The time-dependent growth mechanism from nanoparticles to FFs was observed at optimized parameters such as concentration of precursors, pH (~11), deposition time, and solution temperature. The crystalline nature of CdSSe-FFs is confirmed by high-resolution transmission electron microscopy (HRTEM) results, and selected area electron diffraction (SAED) observations reveal a hexagonal crystal structure. Additionally, the CdSSe-FFs thickness was confirmed by TEM analysis and found to be ~20–30 nm. The optical, photoelectric, and field emission (FE) characteristics are thoroughly explored which shows significant enhancement due to the formation of heterojunction between the gold-coated silicon substrate and CdSSe-FFs. The UV–visible absorption spectra of CdSSe-FFs show enhanced absorption at 700 nm, corresponding to the energy band gap (Eg) of 1.77 eV. The CdSSe-FFs exhibited field emission and photosensitive field emission (PSFE) characteristics. In FE study CdSSe-FFs shows an increase in current density of 387.2 μ A cm−2 in an applied field of 4.1 V m−1 which is 4.08 fold as compared to without light illumination (95.1 μ A cm−2). Furthermore, it shows excellent emission current stability at the preset value of 1.5 μA over 3 h with a deviation of the current density of less than 5% respectively. 相似文献
53.
Qais Ali Al-Maqtari;Norzila Othman;Jalaleldeen Khaleel Mohammed;Amer Ali Mahdi;Waleed Al-Ansi;Abeer Essam Noman;Adel Ali Saeed Al-Gheethi;Syazwani Mohd Asharuddin; 《Food Science & Nutrition》2024,12(10):8255-8279
Artemisia abyssinica and Artemisia arborescens are unique plants that show significant bioactive properties and are used for the treatment of a variety of diseases. This study assessed the nutritional values, functional properties, chemical composition, and bioactive attributes of these plants as functional nutritional supplements. Compared to A. arborescens, A. abyssinica had higher fat (4.76%), fiber (16.07%), total carbohydrates (55.87%), and energy (302.15 kcal/100 g DW), along with superior functional properties, including higher water and oil absorption capacities (638.81% and 425.85%, respectively) and foaming capacity and stability (25.67% and 58.48%). The investigation of volatile compounds found that A. abyssinica had higher amounts of hotrienol (4.53%), yomogi alcohol (3.92%), caryophyllene (3.67%), and carvotanacetone (3.64%), which possess anti-inflammatory, antimicrobial, and antioxidant properties. Artemisia abyssinica contributed over 30% of the recommended dietary intake (RDI) of amino acids. It displayed superior levels of sodium (31.46 mg/100 g DW) and calcium (238.07 mg/100 g DW). It also exhibited higher levels of organic acids, particularly malic acid, butyric acid, and succinic acid, compared to A. arborescens. Fatty acid analysis revealed palmitic and linoleic acids as primary components in both plants, with A. abyssinica having a higher palmitic acid content. Artemisia abyssinica also had higher vitamin C and thiamine levels. Although A. arborescens showed the highest total phenolic content (TPC), antioxidant activity, and capacity, A. abyssinica demonstrated acceptable efficiency in TPC and antioxidant content. These findings highlight the potential of both Artemisia species, particularly A. abyssinica, as valuable sources of nutrients and bioactive compounds for various applications. 相似文献
54.
Mohamed Nihal P;Debasish Mohapatra;Sharfuddin Mohd;Vancha Harish;Sachin Kumar Singh;Gurdeep Singh; 《Journal of Food Safety》2024,44(4):e13155
Mycotoxins are toxic secondary metabolites produced by certain molds and fungi that contaminate various food commodities, posing serious adverse effects on humans and animals. Aflatoxin, ochratoxin, trichothecene, fumonisin, zearalenone, patulin, and citrinin are some of the major mycotoxins affecting food and feed. The scientific community has focused on regulating food and feed materials due to their potential risks. Conventional techniques for mycotoxin detection have certain limitations in terms of sensitivity, specificity, and speed. In recent years, nanotechnology has emerged as a promising approach to revolutionize mycotoxin detection. This review provides an overview of nanotechnology-based detection methods for mycotoxins in food and feed, discussing the basic aspects of mycotoxins, their health hazards, and conventional methods. It also explores various nanosensors and nanodevices developed to improve the sensitivity, selectivity, and speed of mycotoxin detection, thereby enhancing food safety and security. 相似文献
55.
Nur A. A. Rahman Mohd A. Jamlos Mohd F. Jamlos Ping J. Soh Norfatihah Bahari Toufiq M. Hossain 《国际射频与微波计算机辅助工程杂志》2020,30(5)
This article presents a newly circularly polarized (CP) antenna for V2X's dedicated short range communications applications. Its CP characteristic is enabled by a 70 Ω sequential phase feeding network and sequential rotation technique designed on top of the substrate. It has features of ≈90° phase difference in sequence between ports of S21 = 2.4°, S31 = ?87°, S41 = ?180°, and S51 = ?276°, resulting in a 2.19 dB axial ratio centered at 5.9 GHz. The length of the SP feeding network to each ports designed in the different form of meander lines are the key to control the generated phase at the center frequency It also contributes to the smaller final size of 0.59λ × 0.59λ. The proposed antenna operated from 5.850 to 5.925 GHz with a gain between 4 and 6 dBi. The gains are radiated in bidirectional mode due to the presence of the complimentary dipoles located on the opposite side of the substrate. These features indicate the suitability of the proposed antenna in compliance to the ITS‐G5 OBU V2X standard. 相似文献
56.
Mohd Abuzar Sayeed Rajesh Kumar Vishal Sharma 《International Journal of Communication Systems》2020,33(1)
The recent developments in collaborative search, acquisition, and tracking have hoisted the geographical barrier. The network between unmanned aerial vehicles (UAVs) and wireless sensor networks (WSNs) is one such collaboration, which comprises battery‐powered static sensor nodes that act as sources and sinks and UAVs that act as relays. This collaborative network presents with opportunities and advantages, but at the same time, configuration of such networks is an arduous task. The WSN nodes are characterized by constant depleting power. Their network itself requires constant management and reconfiguration. These requisites can be slaked through the formation of an efficient data dissemination algorithm, which acclimates according to the network state. Considering this, a data dissemination approach is presented in this paper, which constructs a virtual topology predicated on the charge of WSN nodes utilizing software‐defined networks (SDNs) through UAVs. The topology is constantly monitored and reconfigured when required. The aerial nodes are equipped with multiple‐input multiple‐output (MIMO) antennas in order to facilitate simultaneous communication with the ground nodes, the base station, and the SDN controller. An efficient sleep timer and backoff counter strategies are also utilized by the proposed approach. The SDN controller facilitates the topology formation and maintenance of a sleep timer and a backoff counter. The proposed model is compared with clustered hierarchical layouts and hexagonal cell layouts through the network simulations. The results suggest significant improvements in the proposed model for various metrics, such as lifetime, delay, latency, delivery ratio, and throughput in comparison with the existing solutions. 相似文献
57.
N.A. Mohd Zahri N.E. Sahira Shafee F. Yusof S. Nurmaya Musa N. Liana Sukiman A.S.M.A. Haseeb Y. Miyashita T. Ariga 《Materialwissenschaft und Werkstofftechnik》2021,52(6):655-663
The porous copper foam was sandwiched between two coppers plate and then brazed using copper-tin (9.7 %)-nickel (5.7 %)-phosphorus (7 %) filler foil. Brazing process was conducted to joint copper/porous copper foam by evaluating the effect of porous copper foam pore densities [pore per inch (PPI)] and brazing holding times. The brazed joint interface of copper and porous copper foam was characterised using Field emission scanning electron microscopy and Energy-dispersive x-ray spectroscopy for the microstructure and elemental composition analysis, respectively. X-ray diffraction analysis was carried out on the shear fractured surfaces of brazed copper and porous copper foam for phase determination. The results exhibited distinct phases of copper (Cu), copper phosphide (Cu3P), nickel phosphide (Ni3P), and copper compound with tin (6 : 5) (Cu6Sn5). The filler layer was formed as an island-shaped that consists of copper phosphide and nickel phosphide. Prolong brazing holding time causes a thinner filler layer in brazing seam. While the non-uniform thickness of the filler layer was observed at different pore densities of porous copper foam. The shear strength of brazed copper/porous copper foam 15 PPI with a 10 min brazing holding time yield a maximum shear strength of 2.9 MPa. 相似文献
58.
59.
A. A. Pauzi M. J. Ghazali S. Mohd Yunus W. F. H. W. Zamri C. H. Azhari S. Husin 《Tribology - Materials, Surfaces & Interfaces》2016,10(2):82-85
Wear is one of the common degradations in a commercial gas turbine. A stainless steel grade 304 (SS 304) fuel nozzle and its collar made of nickel-based superalloy (Hastelloy X) are two vital components that normally suffer from rapid wear. During an installation, the fuel nozzle is slotted into the collar of the combustion liner. In operation, these two surfaces are subjected to high pressure from the fuel combustion, hence continuously rubbing against each other causes vibrations. During the start–stop operation, these surfaces had undergone a large relative motion. The vibration is the main cause of the wear occurrence on the surfaces. Physical properties of the worn surfaces were obtained through visual observations: wear measurement, hardness and microstructure examination. Through visual observations, fretting wear was mainly suspected as the dominant wear mode, particularly after 8,000 of running hours at high temperature and vibration. In short, this paper discusses the preliminary findings of wear on the fuel nozzle and its collar. It also discusses the changes in the mechanical properties before and after the operation. Solutions for mitigating the problem were discussed. 相似文献
60.
Muhammad Ikram Mohammad Naeem Muhammad Zahoor Marlia Mohd Hanafiah Adeleke Abdulrahman Oyekanmi Noor Ul Islam Midrar Ullah Mater H. Mahnashi Amer Al Ali Naif A. Jalal Farkad Bantun Aiman M. Momenah Abdul Sadiq 《International journal of molecular sciences》2022,23(18)
The azo dye orange II is used extensively in the textile sector for coloring fabrics. High concentrations of it are released into aqueous environments through textile effluents. Therefore, its removal from textile wastewater and effluents is necessary. Herein, initially, we tested 11 bacterial strains for their capabilities in the degradation of orange II dye. It was revealed in the preliminary data that B. subtilis can more potently degrade the selected dye, which was thus used in the subsequent experiments. To achieve maximum decolorization, the experimental conditions were optimized whereby maximum degradation was achieved at: a 25 ppm dye concentration, pH 7, a temperature of 35 °C, a 1000 mg/L concentration of glucose, a 1000 mg/L urea concentration, a 666.66 mg/L NaCl concentration, an incubation period of 3 days, and with hydroquinone as a redox mediator at a concentration of 66.66 mg/L. The effects of the interaction of the operational factors were further confirmed using response surface methodology, which revealed that at optimum conditions of pH 6.45, a dye concentration of 17.07 mg/L, and an incubation time of 9.96 h at 45.38 °C, the maximum degradation of orange II can be obtained at a desirability coefficient of 1, estimated using the central composite design (CCD). To understand the underlying principles of degradation of the metabolites in the aliquot mixture at the optimized condition, the study steps were extracted and analyzed using GC-MS(Gas Chromatography Mass Spectrometry), FTIR(Fourier Transform Infrared Spectroscopy), 1H and carbon 13 NMR(Nuclear Magnetic Resonance Spectroscopy). The GC-MS pattern revealed that the original dye was degraded into o-xylene and naphthalene. Naphthalene was even obtained in a pure state through silica gel column isolation and confirmed using 1H and 13C NMR spectroscopic analysis. Phytotoxicity tests on Vigna radiata were also conducted and the results confirmed that the dye metabolites were less toxic than the parent dye. These results emphasize that B. subtilis should be used as a potential strain for the bioremediation of textile effluents containing orange II and other toxic azo dyes. 相似文献