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121.
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
122.
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
123.
A necessary and sufficient condition is derived for certain ad hoc expressions that are frequently used in the literature to represent correctly the degree of polarization of a light beam. 相似文献
124.
Amines used as bases in copper-free, palladium-catalyzed Sonogashira reactions play a multiple role. The oxidative addition of iodobenzene with [Pd(0)(PPh(3))(4)] is faster when performed in the presence of amines (piperidine>morpholine). Amines also substitute one ligand L in trans-[PdI(Ph)(L)(2)] (L=PPh(3), AsPh(3)) formed in the oxidative addition. This reversible reaction, which gives [PdI(Ph)L(R(2)NH)], is favored in the order AsPh(3)>PPh(3) and piperidine>morpholine. Two mechanisms are proposed for Sonogashira reactions, depending on the ligand and the amine. When L=PPh(3), its substitution by the amine in trans-[PdI(Ph)(PPh(3))(2)] is less favored than that of the alkyne. A mechanism involving prior coordination of the alkyne is suggested, followed by deprotonation of the ligated alkyne by the amine. When L=AsPh(3), its substitution in trans-[PdI(Ph)(AsPh(3))(2)] by the piperidine is easier than that by the alkyne, leading to a different mechanism: substitution of AsPh(3) by the amine is followed by substitution of the second AsPh(3) by the alkyne to generate [PdI(Ph)(amine)(alkyne)]. Deprotonation of the ligated alkyne by an external amine leads to the coupling product. This explains why the catalytic reactions are less efficient with AsPh(3) than with PPh(3) as ligand. 相似文献
125.
Chai Fung Chin Boon Aun Teh Amy Amilda Anthony Ismail Aziah Asma Ismail Eugene Boon Beng Ong Theam Soon Lim 《Applied biochemistry and biotechnology》2014,174(5):1897-1906
In our earlier study, an immunoblot analysis using sera from febrile patients revealed that a 50-kDa band from an outer membrane protein fraction of Salmonella enterica serovar Typhi was specifically recognized only by typhoid sera and not sera from other febrile illnesses. Here, we investigated the identities of the proteins contained in the immunogenic 50-kDa band to pinpoint antigens responsible for its immunogenicity. We first used LC-MS/MS for protein identification, then used the online tool ANTIGENpro for antigenicity prediction and produced recombinant proteins of the lead antigens for validation in an enzyme-linked immunosorbent assay (ELISA). We found that proteins TolC, GlpK and SucB were specific to typhoid sera but react to antibodies differently under native and denatured conditions. This difference suggests the presence of linear and conformational epitopes on these proteins. 相似文献
126.
Asma Ait-Kaki Noreddine Kacem-Chaouche Marc Ongena Mounira Kara-Ali Laid Dehimat Karima Kahlat Philippe Thonart 《Applied biochemistry and biotechnology》2014,172(4):1735-1746
This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were screened for their ability to inhibit growth of some phytopathogenic fungi on PDA and some roots exudates. The bacteria identification based on 16S r-RNA and gyrase-A gene sequence analysis showed that 71 % of the screened isolates belonged to Bacillus amyloliquefaciens and the rest were closely related to B. atrophaeus and B. mojavensis. Most of them had high spore yields (22?×?108–27?×?108 spores/ml). They produced protease and cellulase cell wall-degrading enzymes while the chitinase activity was only observed in the B. atrophaeus (6SEL). A wide variety of lipopeptides homologous was detected by liquid chromatography–electrospray ionization–mass spectrometry analysis. Interestingly, some additional peaks with new masses were characterized, which may correspond to new fengycin classes. The isolates produced siderophores and indole-3- acetic acid phytohormone. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. atrophaeus (6SEL) significantly increased the size of the chickpea plants and reduced the stem rot disease (P?<?0.05). These results suggest that these isolates may be used further as bio-inoculants to improve crop systems. 相似文献
127.
In [2, Theorem 3], Bell and Kappe proved that if d is a derivation of a prime ring R which acts as a homomorphism or an anti-homomorphism on a nonzero right ideal I of R, then d = 0 on R. In the present paper our objective is to extend this result to Lie ideals. The following result is proved: Let R be a 2-torsion free prime ring and U a nonzero Lie ideal of R such that u 2 ∈ U, for all u ∈ U. If d is a derivation of R which acts as a homomorphism or an anti-homomorphism on U, then either d=0 or U ?Z(R). 相似文献
128.
Asma Hayat Anwar Latif M. Khaleeq-ur-Rahman K. A. Bhatti Arslan Usman 《辐射效应与固体损伤》2013,168(6):403-409
Laser-induced modifications on platinum (Pt) and silicon (Si) are compared by considering the development of various features on the irradiated surface. The experiments were carried out both in air and under vacuum. The interaction of 50 pulses of 1064 nm Nd:YAG laser with both targets in air resulted in non-linear phenomena. The periphery of the irradiated spot on the Pt surface exhibits wave-like patterns with a featureless central portion. A non-uniform distribution of cones of different sizes is also observed on the irradiated surface. In the case of silicon, the laser-induced periodic surface structures along with the formation of micro-column, rectangular blocks and grid are prominently observed features. However, when both the targets were irradiated with the same number of shots under vacuum (~10?3 Torr), the surface morphologies of both the targets exhibited the hydrodynamic sputtering but with more explosive expulsion in Pt when compared with silicon. In platinum, there is a periodic variation in the distance between adjacent cones formed in various ablated zones. The Gaussian beam mode TEM00 provided the evidences for melt pool formation in silicon when irradiated under vacuum. Additionally, we observed other mechanisms including splashing, sputtering, burning, re-solidification and redeposition on the surface of irradiated targets. 相似文献
129.
The present research was conducted with an aim to develop such adsorbent system: polymer-coated magnetic nanoparticles which can remove heavy metal and dye from water of different concentration. Synthesis of magnetic iron oxide nanoparticles for contaminated water purification has been one of the outcomes of application of rapidly growing field of Nanotechnology in Environmental Science. In the present study, the efficiency of magnetic nanoparticles for removal of Cr(VI) and dye (alizarin) from water solutions of known concentrations were evaluated. The nanoparticles were prepared by co-precipitation method and characterized by X-ray photoelectron spectroscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. Polymer-coated magnetic iron oxide nanoparticles carrying functional groups on their surface were synthesized by different methods for permanent magnet-assisted removal of heavy metal (chromium) and dye (Alizarin Red S) from water. The characterization showed that synthesized nanoparticles were in the size range of 10–50 nm. The adsorption capacities of the Fe3O4 using polyMETAC-coated particles for dye (Alizarin Red S) removal were 80–96 % and chromium 62–91 %. The chromium concentration was determined after magnetic separation using atomic absorption spectrophotometer and dye concentration was estimated with UV–visible spectrophotometer. Nanoparticles of polymer coated showed the highest removal capacity from water for metal and dye. The developed adsorbents had higher capacity for removal of heavy metal ions and dye. 相似文献
130.
M. Syed Ali R. Agalya Bandana Priya Ganesh Kumar Thakur Syeda Asma Kauser 《Mathematical Methods in the Applied Sciences》2022,45(1):561-574
In this paper, the problem of nonlinear multiagent system with reliable control is taken into account. The prescribed system consists of additive time-varying delay, actuator faults with both linear and nonlinear functions. The main focus of this paper is to design a reliable control which guarantees the stability and consensus condition of the proposed system. Actuator faults with linear and nonlinear functions are considered in the control input. From the implementation of integral inequality, the linear matrix inequality format is derived by constructing the suitable Lyapunov Krasovskii functional for the specified system. Terminally numerical examples are furnished for the efficiency of the specified method. 相似文献