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151.
M. Asma A. Bansal W. A. M. Othman B. R. Wong A. Biswas 《Physics of Wave Phenomena》2018,26(4):312-316
Here, optical soliton perturbation with quadratic-cubic nonlinearity has been discussed by applying Lie symmetry and group invariants. The perturbation terms include third and fourth order dispersions in addition to self-steepening, intermodal dispersion and higher order dispersion effects. Using presented algorithms, Bright and dark soliton solutions are revealed. 相似文献
152.
Guillermo Martinez‐Ariza Muhammad Ayaz Sue A. Roberts Walter A. Rabanal‐Len Ramiro Arratia‐Prez Christopher Hulme 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(40):11838-11842
Two structurally unique organocesium carbanionic tetramic acids have been synthesized through expeditious and novel cascade reactions of strategically functionalized Ugi skeletons delivering products with two points of potential diversification. This is the first report of the use of multicomponent reactions and subsequent cascades to access complex, unprecedented organocesium architectures. Moreover, this article also highlights the first use of mild cesium carbonate as a cesium source for the construction of cesium organometallic scaffolds. Relativistic DFT calculations provide an insight into the electronic structure of the reported compounds. 相似文献
153.
154.
Ayaz Mohd W. A. Wan Ab Karim Ghani Nur Zalikha Resitanim Lamin Sanyang 《Journal of Dispersion Science and Technology》2013,34(7):974-984
The changes in global temperatures as a result of carbon dioxide (CO2) emissions has suggested that cumulative CO2 emissions will continue to increase over time. Many countries are looking for ways to reduce or alter the amount of CO2 harming our environment; therefore, this review is a compilation of CO2 adsorption on biomass-derived-biochar (BDB). This suggests that effective measures to mitigate the risk of dangerous climate change will need to limit cumulative emissions of CO2. Further, if cumulative CO2 emissions overshoot acceptable limits, it will become necessary to remove CO2 from the air, that is, the so-called “negative emissions.” In this review, we discuss the definitions and classes of technologies for capturing CO2 from the air and the application of biochar in the improvement of soil fertility. We also discuss the economic tradeoff between biochar and bio-oil, agricultural nutrient leaching, the novel magnetic property of biochar and its durability. 相似文献
155.
Dr. Ruohu Zhang Prof. Dr. Zhuyuan Wang Dr. Chunyuan Song Dr. Jing Yang Dr. Jin Li Dr. Asma Sadaf Prof. Dr. Yiping Cui 《Chemphyschem》2011,12(5):992-998
A new and simple procedure to enhance the fluorescence of analytes on the surfaces of a solid substrate is demonstrated based on Ag@SiO2 nanoparticles. Two kinds of silver–silica core–shell nanoparticles with shell thicknesses of around 3 and 15 nm have been prepared and used as enhancing agents, respectively. By simply pipetting drops of the enhancing agents onto substrate surfaces with Rose Bengal monolayers, an enhancement of about 27 times, compared with the control sample, is achieved by using the Ag@SiO2 nanoparticles with shells of about 3 nm, whereas an enhancement of around 11.7 times is obtained when using those with thicker shells. The effects of shell thickness and surface density of the enhancing agents on the enhancement have been investigated experimentally. The results show that this method can be potentially helpful in fluorescence‐based surface analysis. 相似文献
156.
Shaista Bano Ayaz Mohd Aftab Aslam Parwaz Khan K. S. Siddiqi 《Journal of Analytical Chemistry》2011,66(7):603-609
Simple, accurate, rapid, and sensitive spectrofluorimetric methods for the determination of levosulpiride in pharmaceutical
formulation were developed utilizing its fluorescence reaction with Fe3+ (method A) and Al3+ (method B). The calibration curves were found to be linear in the concentration range 0.239–3.44 μg/mL and 0.310–2.730 μg/mL with limit
of detection 0.005 μg/mL and 0.0032 μg/mL, respectively, for method A and method B. The reaction conditions were studied and optimized. In addition, the complexation of Mg2+ and Ca2+ was also studied. In all cases, an enhancement in fluorescence emission of levosulpiride upon formation of complex with metal
ions was observed. A 2: 1 (drug: metal) stoichiometry for all the complexes was established. Benesi-Hildebrand method was
applied for calculation of association constant at 25 and 35°C. The thermodynamic parameters obtained in this study revealed
that the interaction process was spontaneous and mainly ΔS-driven. 相似文献
157.
Marzouk A Danset D Zhou MF Gong Y Alikhani ME Manceron L 《The journal of physical chemistry. A》2011,115(32):9014-9021
The formation and structure of a novel species, a disuperoxo-cobalt dioxide complex (CoO(6)), has been investigated using matrix isolation in solid neon and argon, coupled to infrared spectroscopy and by quantum chemical methods. It is found that CoO(6) can be formed by successive complexation of cobalt dioxide by molecular oxygen without activation energy by diffusion of ground state O(2) molecules at 9K in the dark. The IR data on one combination and seven fundamentals, isotopic effects, and quantum chemical calculations are both consistent with an asymmetrical structure with two slightly nonequivalent oxygen ligands complexing a cobalt dioxide subunit. Evidence for other, metastable states is also presented, but the data are not complete. The electronic structure and formation pathway of this unique, formally +VI oxidation state, complex has been investigated using several functionals of current DFT within the broken-symmetry unrestricted formalism. It has been shown that the M06L pure local functional well reproduce the experimental observations. The ground electronic state is predicted to be an open shell (2)A' doublet with the quartet states above by more than 9 kcal/mol and the sextet lying even higher in energy. The ground state has a strong and complex multireference character that hinders the use of more precise multireference approaches and requires caution in the methodology to be used. The geometrical, energetic, and vibrational properties have been computed. 相似文献
158.
Ayaz MS Kwak M Alemdaroglu FE Wang J Berger R Herrmann A 《Chemical communications (Cambridge, England)》2011,47(8):2243-2245
Ultra-high molecular weight DNA/polymer hybrid materials were prepared employing molecular biology techniques. Nucleic acid restriction and ligation enzymes were used to generate linear DNA di- and triblock copolymers that contain up to thousands of base pairs in the DNA segments. 相似文献
159.
Asma Mihandoust Nahid Maleki-Jirsaraei Shahin Rouhani Shahabeddin Safi Majid Alizadeh 《Electrophoresis》2020,41(5-6):353-359
The inertial microfluidic technique, as a powerful new tool for accurate cell/particle separation based on the hydrodynamic phenomenon, has drawn considerable interest in recent years. Despite numerous microfluidic techniques of particle separation, there are few articles in the literature on separation techniques addressing external outlet geometry to increase the throughput efficiency and purity. In this work, we report on a spiral inertial microfluidic device with high efficiency (>98%). Herein, we demonstrate how changing the outlet geometry can improve the particle separation throughput. We present a complete separation of 4 and 6 μm from 10 μm particles potentially applicable to separate microalgae (Tetraselmis suecica from Phaeodactylum tricornutum). Two spiral microchannels with the same cross section dimension but different outlet geometry were considered and tested to investigate the particle focusing behavior and separation efficiency. As compared with particle focusing observed in channels with a simple outlet, the particle focusing in a modified outlet geometry appears in a more successful focusing manner with complete separation. This simple approach of particle separation makes it attractive for lab-on-a-chip devices for continuous extraction and filtration of a wide range of cell/particle sizes. 相似文献
160.
Manju Nagaraja Balakrishna Kalluraya Asma Tharangini K. Shreekanth Madan S. Kumar 《Journal of heterocyclic chemistry》2020,57(10):3642-3652
A new class of functionalized pyrazole bearing 1,2,3-triazole has been synthesized via Cu(I) mediated 1,3-dipolar cycloaddition of pyrazole bearing azide with various aromatic/heteroaromatic bearing terminal dipolarophile (acetylene). Structures of the newly synthesized compounds were explicated by analytical and spectral analysis. All the newly synthesized compounds were evaluated for their in-vitro antibacterial and antioxidant activity. Among the synthesized compound, triazole bearing 2,5-thiazolidinone 5b (20 ± 0.70) and triazole bearing thiocarboamide 5e (19 ± 0.70) showed good antibacterial activity against Escherichia coli and Pseudomonas aeruginosa, respectively. The newly synthesized compounds further tested for their ability to bleach DPPH radical using DPPH scavenging assay. Among the synthesized compounds 1,2,3-triazole bearing 2,5-thiazolidinone 5b (58.81%) exhibited good DPPH scavenging activity compared to the rest of the compounds. From the X-ray and Hirshfield analysis, it was observed that compound 3 , crystallizes in a triclinic crystal system with a P-1 space group. The major intercontacts present in these molecules are H…H (39.7%), C…H (23.9%), N…H (20.3%). 相似文献