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81.
Mohd Imran Anis Ahmad Chaudhary Shahzad Ahmed Md. Mottahir Alam Afzal Khan Nasser Zouli Jabir Hakami Hassan Ahmad Rudayni Salah-Ud-Din Khan 《Molecules (Basel, Switzerland)》2022,27(22)
Iron oxide nanoparticle (ION)-based ferro-nanofluids (FNs) have been used for different technological applications owing to their excellent magneto-rheological properties. A comprehensive overview of the current advancement of FNs based on IONs for various engineering applications is unquestionably necessary. Hence, in this review article, various important advanced technological applications of ION-based FNs concerning different engineering fields are critically summarized. The chemical engineering applications are mainly focused on mass transfer processes. Similarly, the electrical and electronics engineering applications are mainly focused on magnetic field sensors, FN-based temperature sensors and tilt sensors, microelectromechanical systems (MEMS) and on-chip components, actuators, and cooling for electronic devices and photovoltaic thermal systems. On the other hand, environmental engineering applications encompass water and air purification. Moreover, mechanical engineering or magneto-rheological applications include dampers and sealings. This review article provides up-to-date information related to the technological advancements and emerging trends in ION-based FN research concerning various engineering fields, as well as discusses the challenges and future perspectives. 相似文献
82.
Abdel Nasser B. Singab Nada M. Mostafa Iten M. Fawzy Deepika Bhatia Pooja Tanaji Suryawanshi Atul Kabra 《Molecules (Basel, Switzerland)》2022,27(19)
Maintaining healthy skin is important for a healthy body. At present, skin diseases are numerous, representing a major health problem affecting all ages from neonates to the elderly worldwide. Many people may develop diseases that affect the skin, including cancer, herpes, and cellulitis. Long-term conventional treatment creates complicated disorders in vital organs of the body. It also imposes socioeconomic burdens on patients. Natural treatment is cheap and claimed to be safe. The use of plants is as old as mankind. Many medicinal plants and their parts are frequently used to treat these diseases, and they are also suitable raw materials for the production of new synthetic agents. A review of some plant families, viz., Fabaceae, Asteraceae, Lamiaceae, etc., used in the treatment of skin diseases is provided with their most common compounds and in silico studies that summarize the recent data that have been collected in this area. 相似文献
83.
Jabbar Khalafy Nasser EtivandShadi Dilmaghani Mahnaz EzzatiAhmad Poursattar Marjani 《Tetrahedron letters》2014
A simple and convenient synthesis of 2-aryl-3-hydroxy-6,7-dihydro-1H-indol-4(5H)-ones is achieved in high yields via the one-pot, three-component reaction of arylglyoxals, 1,3-cyclohexanedione, and ammonium acetate in water under reflux conditions. 相似文献
84.
We analyze in detail an almost optimal algorithm for generating an exponentially distributed variate. The algorithm is due to Knuth and Yao and relies on a method which goes back to J. von Neumann. It is shown here that it can generate k bits of an exponentially distributed variate using an average of about k + 5.67974692 coin flippings. This solves a problem left open by Knuth and Yao. 相似文献
85.
86.
A general synthetic scheme for preparation of thiophosphoramidite intermediates, chloro-N,N-diisopropylaminothiomethoxyphosphine, 2, and 3′-O-deoxythymidine derivatives of N,N-diisopropylaminothiomethoxyphosphine, 4, is described. These intermediates can be used to synthesize dithiophosphate deoxyoligonucleotide analogues. 相似文献
87.
[reaction: see text] A study of published crystal structures (of O-acetylated sugars for the most part) suggests that the exocyclic C-O bond in acetate esters of cyclic alcohols intrinsically prefers a staggered conformation, although the eclipsed conformation is only slightly less stable. When the acetate is flanked by two equatorial substituents the preferred conformation is close to eclipsed. Over 1500 C-OAc bonds have been analyzed. Diagnostic NMR criteria for torsion angles and MM3 calculations are reported and confirm these conclusions. 相似文献
88.
Irradiation of toluence or n-hexanne solutions of dicyclopentadienyldicarbonyldinickel complexes at λ ? 350 nm gives good yields of bridged dinuclear complexes (RCCR′)(CpNi)2. Their bonding and mass spectra are discussed. 相似文献
89.
F.G. Major Y. Makdisi K.S. Bhatia A.A. Zaidi I.H. Nasser Y.A. Yousef 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,34(6):487-492
The radiative lifetime of the 4s 5s (3S1) level in Ca was measured using two-step excitation of atoms in a beam which traverses a cold-cathode Penning discharge, where, by electron impact the atoms are excited to the metastable 4s 5p (3P2, 1, 0) states. Immediately thereafter, the beam is crossed with a pulse-modulated cw dye laser beam to populate the final state selectively. Using a pulse-modulation frequency of 0.5 MHz, a preliminary value of 12.4 ± 0.5 ns was obtained with a statistical error of 0.4%. The wide limits of systematic error reflect an assumed uncertainty in the excitation function and possible distortion in the fluorescence decay requiring further study. 相似文献
90.
Essam Nasser 《Zeitschrift für Physik A Hadrons and Nuclei》1963,172(4):405-428
Extending earlier studies on spark breakdown, the development of the impulse prebreakdown streamers leading to complete breakdown were investigated. By taking advantage of the proportionality between point potential and length of the positive Lichtenberg figure produced, the potential of the streamer tips progressing from a point anode towards a plane cathode were determined. It was found that the streamer tip potential decreases as streamer advances. At voltages much lower than sparking potential this decrease is rapid. By approaching the sparking potential the loss of tip potential diminishes considerably near the anode. The decrease of potential remains very rapid near the cathode until sparking potential is reached. At the cathode the tip potential increases with the applied potential. At a certain value electrons are emitted from the cathode under the influence of high tip fields. These electrons are accelerated towards the tips forming avalanches by collision. These avalanches appear on the photographic film as minute dots whose number and density depend on the intensity of tip fields. If the applied potential exceeds the sparking voltage, tip potentials are recorded on the cathode between 15 and 25 kV. The avalanches formed in the high intensity field region reach the critical size and form negative, anode — directed streamers. These streamers appear on the film as negative Lichtenberg figures. This ionising potential wave, known as return stroke, travels along the channel of the positive primary streamer. It increases its ionisation to such a degree that the main stroke can take place. 相似文献