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991.
In this study, firstly, a double‐reservoir and switchable prototype of a micro‐chip along with the respective holders were fabricated. A cyclic desorption process using microliter volume of organic solvent was adopted to prevent any outdoor contamination. As extractive phases, two identical sheets of electrospun polyamide/polypyrrole/titania nanofibers were synthesized using core–shell electro‐spinning technique and utilized for determination of memantine in plasma samples. Field emission scanning electron microscopy images showed a high degree of porosity and homogeneity throughout the sheet structure. Also, energy dispersive X‐ray analysis confirmed the presence of titania, while the recorded Fourier transform infrared spectra proved the chemical structures of the polymeric mats. The incorporation of titania as well as polypyrrole in the composition of polyamide nanofibers improved both mechanical stability and extraction capacity of the extractive phase and therefore facilitated the extraction/desorption process. The limits of detection and quantification were 0.01 and 0.04 ng/mL, respectively. In addition, the interday and intraday precisions were lower than 6.7% (n = 3). The linearity was in the range of 0.14–75.00 ng/mL, while recoveries were between 94.1 and 98.4% with the regression coefficient of 0.9987. 相似文献
992.
Maryam Asachi Mohammadreza Alizadeh Behjani Ehsan Nourafkan Ali Hassanpour 《Particuology》2021,(1):58-68
The effect of particle shape modification on the segregation reduction of enzyme granules in laundry detergent powder mixtures was investigated,both experimentally and computationally using Deseret Element Method(DEM).The shape of modified enzyme particles was in such a way that the large and dense enzyme particles were layered by other fine particles in the detergent powder,by means of a process known in the literature as“seeded granulation”.It is found that the homogeneity of modified enzyme particles could be improved significantly comparing to the original spherical enzyme particles in powder mixtures.Overall,the results of this research demonstrated that the segregation-induced properties of the dense/spherical enzyme particles could be lowered by altering their shape,which could enable the enzyme particles to behave almost similar to other ingredients during the pile formation process. 相似文献
993.
Peytam Fariba Adib Mehdi Shourgeshty Reihaneh Mohammadi-Khanaposhtani Maryam Jahani Mehdi Imanparast Somaye Faramarzi Mohammad Ali Mahdavi Mohammad Moghadamnia Ali Akbar Rastegar Hossein Larijani Bagher 《Molecular diversity》2020,24(1):69-80
Molecular Diversity - A new series of imidazo[1,2-b]pyrazole derivatives 4a–o was designed, synthesized, and screened for in vitro α-glucosidase inhibitory activity. All compounds showed... 相似文献
994.
Unveiling of Pyrimidindinones as Potential Anti-Norovirus Agents—A Pharmacoinformatic-Based Approach
Oluwakemi Ebenezer Nkululeko Damoyi Maryam A. Jordaan Michael Shapi 《Molecules (Basel, Switzerland)》2022,27(2)
The RNA-dependent RNA polymerase (RdRp) receptor is an attractive target for treating human norovirus (HNV). A computer-aided approach like e-pharmacophore, molecular docking, and single point energy calculations were performed on the compounds retrieved from the Development Therapeutics Program (DTP) AIDS Antiviral Screen Database to identify the antiviral agent that could target the HNV RdRp receptor. Induced-fit docking (IFD) results showed that compounds ZINC1617939, ZINC1642549, ZINC6425208, ZINC5887658 and ZINC32068149 bind with the residues in the active site-B of HNV RdRp receptor via hydrogen bonds, salt bridge, and electrostatic interactions. During the molecular dynamic simulations, compounds ZINC6425208, ZINC5887658 and ZINC32068149 displayed an unbalanced backbone conformation with HNV RdRp protein, while ZINC1617939 and ZINC1642549 maintained stability with the protein backbone when interacting with the residues. Hence, the two new concluding compounds discovered by the computational approach can be used as a chemotype to design promising antiviral agents aimed at HNV RdRp. 相似文献
995.
Maryam Oudi Kazem Sanchooli Tazeh Nourallah Hazeri Maryam Fatahpour Raheleh Ahmadi 《中国化学会会志》2019,66(12):1721-1728
In the present work, the catalytic activity of quinolinic acid (QUIN) was studied for the synthesis of spirochromene and pyranopyrazole derivatives from readily available materials. The salient features of these one‐pot multicomponent protocols are the clean reaction profile, easy isolation of products, no chromatographic separation techniques, high efficiency, short reaction time, and high yield of products plus using QUIN as a new, inexpensive, commercially available, and efficient organocatalyst. 相似文献
996.
In this work, molecularly imprinted nanoparticles (MINPs) were applied as selective adsorbent for ultrasound‐assisted micro‐solid‐phase extraction (UAMSPE) of doxepin (DP) from human plasma samples, which was then cleaned up, pre‐concentrated and subjected to HPLC. The MINPs were synthesized based on a non‐covalent approach by precipitation polymerization utilizing methacrylic acid and styrene as functional monomers, DP as template, ethylene glycol dimethacrylate as cross‐linker and 2,2‐azobisisobutyronitrile (AIBN) as initiator. The obtained MINPs were characterized by Fourier transform‐infrared and field emission scanning electron microscopy. Factors influencing the efficiency of UAMSPE such as sonication time, volume of eluent solvent and amount of sorbent were investigated using a central composite design and the optimal points were identified as 4 min of sonication time, 380 μL of eluent solvent and 30 mg of sorbent. Under optimized conditions, the proposed method has linear responses in the range of 0.2–2000 ng mL–1, with a satisfactory limit of detection of 0.04 ng mL–1 and limit of quantification of 0.11 ng mL–1. 相似文献
997.
Zahra Tanbakouchian Mohammad Ali Zolfigol Behrouz Notash Maryam Ranjbar Morteza Shiri 《应用有机金属化学》2019,33(8)
Four distinct sets of functionalized quinolines were synthesized by reacting 2‐chloroquinoline‐3‐carbonitriles with various types of isocyanides under appropriate conditions. The palladium‐catalysed reaction of less hindered aliphatic and aromatic isocyanides with 2‐chloroquinoline‐3‐carbonitriles yielded 2‐alkyl(aryl)‐1‐imino‐1H‐pyrrolo[3,4‐b]quinolin‐3(2H)‐one derivatives; however, the catalysed reaction of more hindered isocyanides such as tert‐butyl isocyanide produced the corresponding 3‐cyanoquinoline‐2‐carboxamides. Interestingly, chloroquinoline‐3‐carbonitriles reacted with ethyl isocyanoacetate in the presence of Cs2CO3 to generate imidazo[1,5‐a]quinoline derivatives; notably, tosylmethyl isocyanide under the same conditions formed unprecedented 2‐tosyl‐3‐cyanoquinolines. 相似文献
998.
New dinuclear organotin (IV) complexes, Me4Sn2L, Ph4Sn2L and Bu4Sn2L, have been synthesized from reaction of R2SnCl2 (R = Me, Ph and Bu) with a 2,2′‐bis‐substituted diphenylamine arοylidene hydrazone, H4L. The synthesized compounds were investigated by elemental analysis and infrared, 1H‐NMR and 119Sn‐NMR spectroscopy. The structures of H4L, Me4Sn2L and Bu4Sn2L were also confirmed by X‐ray crystallography. H4L molecules adopt (E)‐configuration and keto‐tautomeric form in the solid state. In all complexes, the bis‐hydrazone acts as a tetra‐anionic ligand with two contiguous ONO tridentate domains that coordinate the two R2Sn moieties in the enolate form. The coordination environments of both tin centers are five‐coordinate. DNA‐binding studies were performed by UV–Vis spectroscopy, and the results indicate that the synthesized compounds significantly interact with calf thymus‐DNA in the intercalative mode. The results of polymerase chain reaction assay show that all the compounds affect on amplification of DNA, and complexes are more effective than ligands. The in vitro cytotoxicity against the human breast cancer line (MCF7) was determined using the MTT assay, and H4L and the dibutytin complex showed higher activity. 相似文献
999.
Structural Chemistry - We applied density functional theory calculations to study reactions NH2 ?+ SinHn fullerenes (n?=?4, 6, 8, 10, 20, 24, 30, 36, and 50). The reactions... 相似文献
1000.
Frontispiece: Lewis Acid Guests in a {P8W48} Archetypal Polyoxotungstate Host: Enhanced Proton Conductivity via Metal‐Oxo Cluster within Cluster Assemblies
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