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Sanaz Khan-Afshar Umair Siddique Mohamed Yousri Mahmoud Vincent Aravantinos Ons Seddiki Osman Hasan Sofiène Tahar 《Mathematics in Computer Science》2014,8(1):39-70
Optical systems are becoming increasingly important by resolving many bottlenecks in today’s communication, electronics, and biomedical systems. However, given the continuous nature of optics, the inability to efficiently analyze optical system models using traditional paper-and-pencil and computer simulation approaches sets limits especially in safety-critical applications. In order to overcome these limitations, we propose to employ higher-order-logic theorem proving as a complement to computational and numerical approaches to improve optical model analysis in a comprehensive framework. The proposed framework allows formal analysis of optical systems at four abstraction levels, i.e., ray, wave, electromagnetic, and quantum. 相似文献
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Siraj Uddin Luqman Bin Safdar Saeed Anwar Javed Iqbal Sabiha Laila Banzeer Ahsan Abbasi Muhammad Saqib Saif Musrat Ali Abdul Rehman Abdul Basit Yong Wang Umar Masood Quraishi 《Molecules (Basel, Switzerland)》2021,26(6)
Green synthesis of nanomaterials is advancing due to its ease of synthesis, inexpensiveness, nontoxicity and renewability. In the present study, an eco-friendly biogenic method was developed for the green synthesis of nickel oxide nanoparticles (NiONPs) using phytochemically rich Berberis balochistanica stem (BBS) extract. The BBS extract was rich in phenolics, flavonoids and berberine. These phytochemicals successfully reduced and stabilised the NiNO3 (green) into NiONPs (greenish-gray). BBS-NiONPs were confirmed by using UV-visible spectroscopy (peak at 305 nm), X-ray diffraction (size of 31.44 nm), Fourier transform infrared spectroscopy (identified -OH group and Ni-O formation), energy dispersive spectroscopy (showed specified elemental nature) and scanning electron microscopy (showed rhombohedral agglomerated shape). BBS-NiONPs were exposed to multiple in vitro bioactivities to ascertain their beneficial biological applications. They exhibited strong antioxidant activities: total antioxidant capacity (64.77%) and 2, 2-diphenyl-1-picrylhydrazyl (71.48%); and cytotoxic potential: Brine shrimp cytotoxicity assay with IC50 (10.40 µg/mL). BBS-NiONPs restricted the bacterial and fungal pathogenic growths at 1000, 500 and 100 µg/mL. Additionally, BBS-NiONPs showed stimulatory efficacy by enhancing seed germination rate and seedling growth at 31.25 and 62.5 µg/mL. In aggregate, BBS extract has a potent antioxidant activity which makes the green biosynthesis of NiONPs easy, economical and safe. The biochemical potential of BBS-NiONPs can be useful in various biomedical and agricultural fields. 相似文献
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Anwar Iqbal Usman Saidu Farook Adam Srimala Sreekantan Noorfatimah Yahaya Mohammad Norazmi Ahmad Rajabathar Jothi Ramalingam Lee D. Wilson 《Molecules (Basel, Switzerland)》2021,26(9)
In this work, mesoporous TiO2-modified ZnO quantum dots (QDs) were immobilised on a linear low-density polyethylene (LLDPE) polymer using a solution casting method for the photodegradation of tetracycline (TC) antibiotics under fluorescent light irradiation. Various spectroscopic and microscopic techniques were used to investigate the physicochemical properties of the floating hybrid polymer film catalyst (8%-ZT@LLDPE). The highest removal (89.5%) of TC (40 mg/L) was achieved within 90 min at pH 9 due to enhanced water uptake by the LDDPE film and the surface roughness of the hybrid film. The formation of heterojunctions increased the separation of photogenerated electron-hole pairs. The QDs size-dependent quantum confinement effect leads to the displacement of the conduction band potential of ZnO QDs to more negative energy values than TiO2. The displacement generates more reactive species with higher oxidation ability. The highly stable film photocatalyst can be separated easily and can be repeatedly used up to 8 cycles without significant loss in the photocatalytic ability. The scavenging test indicates that the main species responsible for the photodegradation was O2●−. The proposed photodegradation mechanism of TC was demonstrated in further detail based on the intermediates detected by LC-time-of-flight/mass spectrometry (LC/TOF-MS). 相似文献
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Mashooq A. Bhat Ahmed M. Naglah Siddique Akber Ansari Hanaa M. Al-Tuwajiria Abdullah Al-Dhfyan 《Molecules (Basel, Switzerland)》2021,26(12)
A ChCl: Gly (DESs) promoted environmentally benign method was developed for the first time using the reaction of aryl aldehydes and dimedone to give excellent yields of xanthene analogues. The major application of this present protocol is the use of green solvent, a wide range of substrate, short reaction times, ease of recovery, the recyclability of the catalyst, high reaction yield, and ChCl: Gly as an alternative catalyst and solvent. In addition to this, all the synthesized compounds were evaluated for their in vitro antimycobacterial activity against M. tuberculosis H37Ra (MTB) and M. bovis BCG strains. The compounds 3d, 3e, 3f, and 3j showed significant antitubercular activity against MTB and M. bovis strains with minimum inhibitory concentration (MIC) values of 2.5−15.10 µg/mL and 0.26–14.92 µg/mL, respectively. The compounds 3e, 3f, and 3j were found to be nontoxic against MCF-7, A549, HCT 116, and THP-1 cell lines. All the prepared compounds were confirmed by 1H NMR and 13C NMR analysis. 相似文献
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Kamal Tahseen Khan Sher Bahadar Bakhsh Esraa M. Anwar Yasir 《Cellulose (London, England)》2021,28(17):11067-11080
Cellulose - In this research work, we present a synthesis of silver and cobalt bimetal nanoparticles stabilized by a carboxymethyl cellulose biopolymer (CMC-AgCo) and its coating on a cellulose... 相似文献
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Rate Coefficients of C1 and C2 Criegee Intermediate Reactions with Formic and Acetic Acid Near the Collision Limit: Direct Kinetics Measurements and Atmospheric Implications 下载免费PDF全文
Dr. Oliver Welz Dr. Arkke J. Eskola Dr. Leonid Sheps Dr. Brandon Rotavera Dr. John D. Savee Dr. Adam M. Scheer Dr. David L. Osborn Dr. Douglas Lowe Dr. A. Murray Booth Ping Xiao Dr. M. Anwar H. Khan Prof. Carl J. Percival Prof. Dudley E. Shallcross Dr. Craig A. Taatjes 《Angewandte Chemie (International ed. in English)》2014,53(18):4547-4550
Rate coefficients are directly determined for the reactions of the Criegee intermediates (CI) CH2OO and CH3CHOO with the two simplest carboxylic acids, formic acid (HCOOH) and acetic acid (CH3COOH), employing two complementary techniques: multiplexed photoionization mass spectrometry and cavity‐enhanced broadband ultraviolet absorption spectroscopy. The measured rate coefficients are in excess of 1×10?10 cm3 s?1, several orders of magnitude larger than those suggested from many previous alkene ozonolysis experiments and assumed in atmospheric modeling studies. These results suggest that the reaction with carboxylic acids is a substantially more important loss process for CIs than is presently assumed. Implementing these rate coefficients in global atmospheric models shows that reactions between CI and organic acids make a substantial contribution to removal of these acids in terrestrial equatorial areas and in other regions where high CI concentrations occur such as high northern latitudes, and implies that sources of acids in these areas are larger than previously recognized. 相似文献