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101.
Laila A. Al-Mutabagani Latifah A. Alshabanah Hoda A. Ahmed Hafsa H. Alalawy Mayada H. Al alwani 《Molecules (Basel, Switzerland)》2021,26(7)
Homolog series based on three aromatic rings bearing terminal alkoxy chain of various lengths named 4-(4-(alkoxy)phenylimino)methyl)phenyl nicotinate (An) were synthesized. The alkoxy-chain length changed between 6, 8 and 16 carbons. Mesomorphic and optical properties were carried out via differential scanning calorimetry (DSC) and polarized optical microscopy (POM). Elemental analyses, FT-IR and NMR spectroscopy were carried out to elucidate the molecular structures of the prepared derivatives. Mesomorphic results indicated that all the synthesized homologs (An) are monomorphic possessing the nematic (N) phase enantiotropically with wide thermal stability. Computational simulations were measured via density functional theory (DFT) theoretical calculation tool. The estimated thermal and geometrical parameters are in agreement with the experimental data. By discussing the estimated parameters, it was found that the molecular architecture, dipole moment and the polarizability of the investigated compounds are highly affected by the length of the attached terminal flexible chain and the location of the nitrogen atom in the other terminal aromatic ring. Binary phase diagrams of two corresponding homologs with different proportionating terminals were constructed, and their binary phase physical properties were discussed in terms of the temperature range and stability of the N phase. 相似文献
102.
Shiripoure Ganjineh Ketab Roghayeh Tafvizi Farzaneh Khodarahmi Parvin 《Journal of Cluster Science》2021,32(5):1389-1399
Journal of Cluster Science - Since green synthesis of silver nanoparticles (AgNPs) is a simple, safe, cost-effective and eco-friendly method, AgNPs appear to be promising anti-cancer agents in the... 相似文献
103.
Differential optical absorption spectroscopy-based refractive index sensor for cancer cell detection
Parvin Tarunnum Ahmed Kawsar Alatwi Aadel M. Rashed Ahmed Nabih Zaki 《Optical Review》2021,28(1):134-143
Optical Review - A novel spectroscopic optical sensor is presented for cancerous cell detection in various parts of the human body (i.e., cervix, adrenal gland, breast, skin, and blood). An... 相似文献
104.
Seyedeh Yasaman Afsar Ghodsi Mohammadi Ziarani Hoda Mollabagher Parisa Gholamzadeh Alireza Badiei Ali Abolhasani Soorki 《Journal of the Iranian Chemical Society》2017,14(3):577-583
An efficient one-pot synthesis of 2,3-dihydroquinazoline-4(1H)-one derivatives 4a–l is described using SBA-Pr-SO3H as a heterogeneous acid catalyst. The present methodology resulted in various derivatives of 2,3-dihydroquinazoline-4(1H)-one in good yield via a three-component reaction of isatoic anhydride, aldehydes and ammonium acetate. SBA-Pr-SO3H played a significant role as an efficient mesoporous catalyst due to its pore size of 6 nm. Additionally, UV–Vis spectrum of the products was studied in order to investigate their application as UV absorbers. 相似文献
105.
The structure, 14N NQR parameters, electronic spectra, and hyperplarizability of [Cr(CO)5py] in seven different solvents were theoretically computed with MPW1PW91 method based on Polarizable Continuum Model (PCM). The substituent effects in para- substituted Cr(CO)5–pyridine complexes have been evaluated. The results indicate that both polarity of solvents and the substituents have played a significant role on the structures and properties of complexes. The study also shows that the structural and solvent modification change the NLO properties. 相似文献
106.
One‐pot Synthesis of Highly Functionalized Tetrahydropyridines: A Camphoresulfonic Acid Catalyzed Multicomponent Reaction
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A simple and straight forward solvent free method for the synthesis of a series of highly functionalized tetrahydropyridine derivatives has been achieved via multicomponent reaction of aromatic aldehydes, various amines, and β‐keto esters at room temperature using readily available (±)‐camphor‐10‐sulfonic acid as an organocatalyst. The current protocol offers an atom economic and environmentally benign method for the synthesis of the title compounds under solvent free conditions in good yields with high substrate scope and avoids column chromatographic purification. 相似文献
107.
Simultaneous Determination of Ascorbic Acid,Dopamine and Uric Acid,at a Graphene Paste Electrode Modified with Functionalized Graphene Sheets
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Mohammad Hadi Parvin 《Electroanalysis》2015,27(6):1394-1402
The present study reports the simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA) in phosphate buffer solution (pH 7.0) using graphene paste electrode modified with functionalized graphene sheets (GPE‐MFGSs). The presence of FGS inhibited the adsorption of AA owing to the electrostatic repulsion, but was favorable for the affinity adsorption of DA and UA via the ion exchange and hydrogen bonding mechanisms, respectively. This led to the decrease in the oxidation potential of AA and the significantly enhanced oxidation peak currents of DA and UA at the GPE‐MFGSs. By cyclic voltammetry and differential pulse voltammetry, the oxidation potentials of AA, DA, and UA, at the GPE‐MFGSs in a ternary mixture were found to be well resolved so that their simultaneous determination could be achieved. Furthermore, the influence of some experimental variables such as graphene paste composition, working solution pH, scan rate and pulse amplitude was studied. In addition, by differential pulse voltammetry, the linear dependence of peak current on the concentration was obtained in the ranges of 0.05–9.0, 0.03–13, and 0.03–5.5 µM with the lowest detection limits of 0.02, 0.01, and 0.01 µM for AA, DAand UA, , respectively. 相似文献
108.
Quantitative Measurement of Transmitters in Individual Vesicles in the Cytoplasm of Single Cells with Nanotip Electrodes
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Johan Dunevall Hoda Fathali Prof. Andrew G. Ewing 《Angewandte Chemie (International ed. in English)》2015,54(41):11978-11982
The quantification of vesicular transmitter content is important for studying the mechanisms of neurotransmission and malfunction in disease, and yet it is incredibly difficult to measure the tiny amounts of neurotransmitters in the attoliter volume of a single vesicle, especially in the cell environment. We introduce a novel method, intracellular vesicle electrochemical cytometry. A nanotip conical carbon‐fiber microelectrode was used to electrochemically measure the total content of electroactive neurotransmitters in individual nanoscale vesicles in single PC12 cells as these vesicles lysed on the electrode inside the living cell. The results demonstrate that only a fraction of the quantal neurotransmitter content is released during exocytosis. These data support the intriguing hypothesis that the vesicle does not open all the way during the normal exocytosis process, thus resulting in incomplete expulsion of the vesicular contents. 相似文献
109.
An environmentally friendly synthesis method for bis(indolyl)methanes has been developed in the presence of sodium lauryl ether sulfate(SLES),electrophilic substitution reactions of indoles with aldehydes were accomplished in water as solvent at room temperature without any Bronested or Lewis acid catalysts. 相似文献
110.
Parvin Sarabadani Mahdi Sadeghi Mohamadreza Ghasemi Zargham Asadollahi Narges Afshari 《Journal of Cluster Science》2011,22(2):131-140
High purity tin oxide nanopowders have been synthesized by using a solid-state chemical reaction technique with annealing
at elevated temperature. The effects of two parameters, specifically by controlling the annealing temperature and kind of
alkaline chlorides as precursors, the effect on particle size, morphology and IR spectra of synthesized tin oxide nanopowder
were investigated. From the X-ray pattern, the crystal structure of the synthesized powders was confirmed as a tetragonal
structure. Based on the recorded FTIR spectrum of SnO2, the IR bands due to SnO2 vibrations and its lattice modes were observed at 625 and 690 cm−1, respectively. In addition, an important characterization peak has been identified at 1,450 cm−1 due to Sn–O–Sn bridges observed only when LiCl was used as precursor. The formation of Sn–O–Sn bridges was confirmed by TGA–DTA
analysis. According to the SEM images, it is obvious to notice that the kind of alkaline chlorides as precursors play a dominant
role in controlling the morphology of tin oxide nanopowders. 相似文献