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https://www.readbyqxmd.com/read/28434062/nlophoric-3-6-di-substituted-quinoxalin-carbazoles-synthesis-photophysical-properties-and-dft-studies
#1
Rahul D Telore, Amol G Jadhav, Nagaiyan Sekar
Synthesis of novel 3,6-di(substituted quinoxalin) carbazole fluorophores by the condensation of 1,1'-(9-ethyl-9H-carbazole-3,6-diyl)bis(2-bromoethanone) with methyl, chloro and unsubstituted o-phenylenediamine is presented. Synthesized derivatives are well characterized by (1)H NMR, (13)C NMR, FTIR and Mass spectroscopy. Photophysical studies are carried out using solvents of varying polarities revealed positive solvatochromism and intramolecular charge transfer from carbazole (Donor) to quinoxalin (Acceptor)...
April 22, 2017: Journal of Fluorescence
https://www.readbyqxmd.com/read/28433942/synthesis-and-characterization-of-poly-propylene-imine-dendrimer-grafted-gold-nanoparticles-as-nanocarriers-of-doxorubicin
#2
Marzieh Golshan, Mehdi Salami-Kalajahi, Mina Mirshekarpour, Hossein Roghani-Mamaqani, Maryam Mohammadi
The aim of current work is synthesis 4th-generation-poly(propylene imine) (PPI)-dendrimer modified gold nanoparticles (Au-G4A) as nanocarriers for doxorubicin (DOX) and studying in vitro drug release kinetics from nanocarriers into different media. Accordingly, AuNPs were synthesized by reduction of chloroauric acid (HAuCl4) aqueous solution with trisodium citrate and modified with cysteamine to obtain amine-functionalized (Au-NH2) nanoparticles. Au-NH2 nanoparticles were used as multifunctional cores and participated in Michael addition of acrylonitrile and reduction process by lithium aluminum hydride (LAH) to synthesize Au-G4A nanoparticles...
April 13, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28433922/effects-of-aging-on-prefrontal-brain-activation-during-challenging-walking-conditions
#3
Anat Mirelman, Inbal Maidan, Hagar Bernad-Elazari, Shiran Shustack, Nir Giladi, Jeffrey M Hausdorff
BACKGROUND: Deficits in cognitive domains, in particular, those related to the prefrontal cortex, contribute to diminished walking performance in complex conditions in older age. Studies using functional near infra-red spectroscopy (fNIRS) reported inconsistent findings of brain activation age-related changes in response to increased task demands. We aimed to study the effects of aging on gait and prefrontal activation in complex walking tasks with internal and external task demands. METHODS: Twenty-three healthy young adults (30...
April 20, 2017: Brain and Cognition
https://www.readbyqxmd.com/read/28433872/biosynthesis-of-silver-nanoparticles-by-using-camellia-japonica-leaf-extract-for-the-electrocatalytic-reduction-of-nitrobenzene-and-photocatalytic-degradation-of-eosin-y
#4
R Karthik, Mani Govindasamy, Shen-Ming Chen, Yi-Hui Cheng, P Muthukrishnan, S Padmavathy, A Elangovan
In the present study, sphere-like silver nanoparticles (Ag-NPs) were synthesized by using Camellia japonica leaf extract and its remediation industrial pollutants such as nitrobenzene and Eosin-Y (EY). As-prepared sphere-like Ag-NPs were characterized by various analytical and spectroscopic methods such as UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), High-resolution transmission electron microscopy (HR-TEM), Energy dispersive X-ray spectra (EDX), and the chemical constituents of the leaf extract were also analyzed by using Gas chromatography and Mass Spectroscopy (GC-MS)...
March 28, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28433858/reduced-graphene-oxide-chitosan-aptamer-interface-as-new-platform-for-ultrasensitive-detection-of-human-epidermal-growth-factor-receptor-2
#5
Arezoo Tabasi, Abdollah Noorbakhsh, Ensiyeh Sharifi
The present work describes an ultrasensitive electrochemical aptamer-based assay for detection of human epidermal growth factor receptor 2 protein (HER2) cancer biomarker as a model analyte. Results show that the reduced graphene oxide-chitosan (rGO-Chit) film as a suitable electrode material possesses great favorable properties including high homogeneity, good stability, large surface area and high fraction of amine groups as aptamer binding sites. Various steps of aptasensor fabrication were characterized using microscopic, energy-dispersive X-ray spectroscopy (EDAX), Fourier transform infrared (FTIR) spectroscopy and electrochemical techniques...
April 18, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28433834/antimicrobial-and-anticancer-photodynamic-activity-of-a-phthalocyanine-photosensitizer-with-n-methyl-morpholiniumethoxy-substituents-in-non-peripheral-positions
#6
Jolanta Dlugaszewska, Wojciech Szczolko, Tomasz Koczorowski, Paulina Skupin-Mrugalska, Anna Teubert, Krystyna Konopka, Malgorzata Kucinska, Marek Murias, Nejat Düzgüneş, Jadwiga Mielcarek, Tomasz Goslinski
Photodynamic therapy involves the use of a photosensitizer that is irradiated with visible light in the presence of oxygen, resulting in the formation of reactive oxygen species. A novel phthalocyanine derivative, the quaternary iodide salt of magnesium(II) phthalocyanine with N-methyl morpholiniumethoxy substituents, was synthesized, and characterized. The techniques used included mass spectrometry (MALDI TOF), UV-vis, NMR spectroscopy, and photocytotoxicity against bacteria, fungi and cancer cells. The phthalocyanine derivative possessed typical characteristics of compounds of the phthalocyanine family but the effect of quaternization was observed on the optical properties, especially in terms of absorption efficiency...
April 8, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28433833/in-vitro-antitumor-activity-metal-uptake-and-reactivity-with-ascorbic-acid-and-bsa-of-some-gold-iii-complexes-with-n-n-ethylenediamine-bidentate-ester-ligands
#7
Nebojša Pantelić, Bojana B Zmejkovski, Branka Kolundžija, Marija Đorđić Crnogorac, Jelena M Vujić, Biljana Dojčinović, Srećko R Trifunović, Tatjana P Stanojković, Tibor J Sabo, Goran N Kaluđerović
Four novel gold(III) complexes of general formulae [AuCl2{(S,S)-R2eddl}]PF6 (R2eddl=O,O'-dialkyl-(S,S)-ethylenediamine-N,N'-di-2-(4-methyl)pentanoate, R=n-Pr, n-Bu, n-Pe, i-Bu; 1-4, respectively), were synthesized and characterized by elemental analysis, UV/Vis, IR, and NMR spectroscopy, as well as high resolution mass spectrometry. Density functional theory calculations pointed out that (R,R)-N,N'-configuration diastereoisomers were energetically the most favorable. Duo to high cytotoxic activity complex 3 was chosen for stability study in DMSO, no decomposition occurs within 24h, and for the reaction with ascorbic acid in which was reduced immediately...
April 4, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28433700/isotopic-characterization-and-thermal-neutron-flux-determination-of-a-pube-neutron-source
#8
Ravi Ankit Purty, Akanchha, Shikha Prasad
The Indian Institute of Technology Kanpur (IIT Kanpur) possesses a PuBe neutron source facility with an initial activity of 5 Ci, dated September 1966 (nearly 50 years ago). An understanding of the present activity and the rate of its change will allow implementation of proper radiological safety procedures and future radiological safety planning. Knowing the absolute neutron flux will help us in future neutron activation studies. These details are also important to ensure proper security precautions. In our work, we attempt to identify the isotopic composition to determine the rate of change of the source and the absolute thermal neutron flux of plutonium beryllium (PuBe) sample at IIT Kanpur...
April 5, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28433479/modeling-short-range-substitution-order-and-disorder-in-crystals-application-to-the-ga-si-distribution-in-a-natrolite-zeolite
#9
Sylvian Cadars, Nak Ho Ahn, Kirill Okhotnikov, Jiho Shin, Aurélie Vicente, Suk Bong Hong, Christian Fernandez
Atomic substitutions are a central feature of the physicochemical properties of an increasing number of solid-state materials. The complexity that this chemical disorder locally generates in otherwise crystalline solids poses a major challenge to the understanding of the relationships between the structure and properties of materials at the atomic and molecular level. Strategies designed to efficiently explore the ensemble of local chemical environments present in disordered crystals and predict their signatures in local spectroscopies such as solid-state nuclear magnetic resonance (NMR) are therefore essential...
April 13, 2017: Solid State Nuclear Magnetic Resonance
https://www.readbyqxmd.com/read/28433178/preparation-and-characterization-of-biodegradable-nanocomposites-derived-from-carboxymethyl-cellulose-and-hydroxyapatite
#10
K Azzaoui, E Mejdoubi, A Lamhamdi, S Jodeh, O Hamed, M Berrabah, S Jerdioui, R Salghi, N Akartasse, A Errich, Á Ríos, M Zougagh
Development of a cost-effective technology for extraction and quantification of carcinogenic and toxic organic materials which are widely used in the industry are critical to humans. Membrane technology received much attention and has already been widely used in this area. In this work, we offer a newly developed bio-based nanocomposite membrane for removal of bisphenol-A (BPA) from water. Three natural components hydroxyapatite (HAp), carboxymethyl cellulose and lysine as a diluent were used for making the bio-based membrane...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433170/structural-characterization-and-immuno-enhancing-activity-of-a-highly-branched-water-soluble-%C3%AE-glucan-from-the-spores-of-ganoderma-lucidum
#11
Yatao Wang, Yanfang Liu, Huazheng Yu, Shuai Zhou, Zhong Zhang, Di Wu, Mengqiu Yan, Qingjiu Tang, Jingsong Zhang
A water soluble β-glucan (GLSWA-I) with a weight average molecular weight ∼1.57×10(5)g/mol, isolated from the aqueous extract of the broken cellular wall Ganoderma lucidum spores, was purified by anion-exchange and gel-permeation chromatography. The immunological activity test in vivo showed that GLSWA-I could significantly promote dinitrochlorobenzene (DNCB) induced delayed-type ear swelling in mice. Based on the monosaccharides composition analysis, methylation analysis, IR, 1D and 2D NMR spectroscopy, the repeating unit of polysaccharide GLSWA-I was elucidated as follows...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433164/characterization-and-application-of-cellulose-acetate-synthesized-from-sugarcane-bagasse
#12
R G Candido, G G Godoy, Adilson R Gonçalves
The synthesis and application of cellulose acetate (CA) from sugarcane bagasse were investigated. Firstly, cellulose was extracted by a sequential treatment with H2SO4 (10% v/v), NaOH (5% w/v), EDTA (0.5% w/V), and H2O2 (5% v/v), and characterized by X-ray diffraction (DRX). After the acetylation of the extracted cellulose, CA was characterized using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetry analysis (TGA), and was applied in the membrane production...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433156/ternary-natural-deep-eutectic-solvent-nades-infused-phthaloyl-starch-as-cost-efficient-quasi-solid-gel-polymer-electrolyte
#13
Vidhya Selvanathan, Ahmad Danial Azzahari, Adyani Azizah Abd Halim, Rosiyah Yahya
A first-of-its-kind, eco-friendly quasi-solid bioelectrolyte derived from potato starch was prepared. Starch was chemically modified via phthaloylation to synthesize amorphous, hydrophobic starch derivative and the attachment of the phthaloyl group was confirmed via FTIR which showed phthalate ester peak at 1715cm(-1); and (1)H NMR peaks between 7.30-7.90ppm attributed to the aromatic protons of the phthaloyl group. The resulting starch derivative was then infused with ternary natural deep eutectic solvent (NADES) made from different molar ratios of choline chloride, urea and glycerol...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433154/non-immunogenic-porous-and-antibacterial-chitosan-and-antheraea-mylitta-silk-sericin-hydrogels-as-potential-dermal-substitute
#14
Sunaina Sapru, Ananta K Ghosh, Subhas C Kundu
Limitation of existing grafts including restricted donor site, risks of immune reactions, infectious diseases and high cost alarms the growing need of natural, cost effective and functional graft as the dermal substitute. We fabricate stable (>6 weeks) and porous (57.23-75.22μm) yet flexible (in variable pH) matrices using Antheraea mylitta sericin crosslinked with well known biocompatible polysaccharide chitosan by natural crosslinker (genipin) without using any harsh chemical. The fabricated matrices are characterized in terms of chemical modifications (Fourier transform infrared spectroscopy), crystallinity (X-ray diffraction), swelling, degradability and thermal stability...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433153/polyethylenimine-kappa-carrageenan-micro-arc-oxidation-coating-for-passivation-of-magnesium-alloy
#15
A Golshirazi, M Kharaziha, M A Golozar
The aim of this study was to combine micro-arc oxidation (MAO) and self-assembly technique to improve corrosion resistivity of AZ91 alloy. While a silicate-fluoride electrolyte was adopted for MAO treatment, polyethylenimine (PEI)/kappa carrageenan (KC) self-assembly coating was applied as the second coating layer. Resulted demonstrated the formation of forsterite-fluoride containing MAO coating on AZ91 alloy depending on the voltage and time of anodizing process. Addition of the second PEI/KC coating layer on MAO treated sample effectively enhanced the adhesive strength of MAO coated sample due to filling the pores with polymers and increase in the mechanical interlocking of coating to the substrate...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433147/mucopolysaccharide-from-cuttlefish-purification-chemical-characterization-and-bioactive-potential
#16
Palaniappan Seedevi, Meivelu Moovendhan, Shanmugam Vairamani, Annaian Shanmugam
The sulfated mucopolysaccharide (GAG) was isolated from S. pharonis and the carbohydrate and protein content was found to be 62.4% and 3.9%. The disaccharide profile of sulfated GAG composed glucuronic acid, N-acetyl glucosamine and sulfate content by contributing 50.11%, 38.00% and 27.69% respectively. The carbon, hydrogen and nitrogen content of the sulfated GAG showed 14.80%, 1.68% and 2.99% respectively. The molecular weight of sulfated GAG was calculated as 27kDa and the structural characterization was done by Fourier Transform Infrared (FT-IR) and NMR Spectroscopy...
July 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28433061/graphene-coated-polymeric-anion-exchangers-for-ion-chromatography
#17
Kai Zhang, Minyi Cao, Chaoyan Lou, Shuchao Wu, Peimin Zhang, Mingyu Zhi, Yan Zhu
Carbonaceous stationary phases have gained much attention for their peculiar selectivity and robustness. Herein we report the fabrication and application of a graphene-coated polymeric stationary phase for anion exchange chromatography. The graphene-coated particles were fabricated by a facile evaporation-reduction method. These hydrophilic particles were proven appropriate substrates for grafting of hyperbranched condensation polymers (HBCPs) to make pellicular anion exchangers. The new phase was characterized by zeta potentials, Fourier transform infrared spectroscopy, thermogravimetry and scanning electron microscope...
June 1, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28433038/four-dimensional-coherent-electronic-raman-spectroscopy
#18
Elad Harel
The correlations between different quantum-mechanical degrees of freedom of molecular species dictate their chemical and physical properties. Generally, these correlations are reflected in the optical response of the system but in low-order or low-dimensionality measurement the signals are highly averaged. Here, we describe a novel four-dimensional coherent spectroscopic method that directly correlates within and between the manifold of electronic and vibrational states. The optical response theory is developed in terms of both resonant and non-resonant field-matter interactions...
April 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28433032/ir-spectral-assignments-for-the-hydrated-excess-proton-in-liquid-water
#19
Rajib Biswas, William Carpenter, Joseph A Fournier, Gregory A Voth, Andrei Tokmakoff
The local environmental sensitivity of infrared (IR) spectroscopy to a hydrogen-bonding structure makes it a powerful tool for investigating the structure and dynamics of excess protons in water. Although of significant interest, the line broadening that results from the ultrafast evolution of different solvated proton-water structures makes the assignment of liquid-phase IR spectra a challenging task. In this work, we apply a normal mode analysis using density functional theory of thousands of proton-water clusters taken from reactive molecular dynamics trajectories of the latest generation multistate empirical valence bond proton model (MS-EVB 3...
April 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28433025/a-combined-theoretical-and-experimental-study-of-phenol-acetylene-n-n-%C3%A2-7-clusters
#20
Gurmeet Singh, Apurba Nandi, Shridhar R Gadre, Takashi Chiba, Asuka Fujii
Structures and vibrational spectra of phenol-(acetylene)n (Ph(Ac)n) clusters are studied by a combination of theoretical calculations and infrared (IR) spectroscopy. The molecular electrostatic potential features are utilized for generating trial geometries of the medium-sized Ph(Ac)n (n = 1, 2, 4, 6, and 7) clusters. These initial geometries are subjected to geometry optimization within the second-order Møller-Plesset (MP2) theory, employing correlation consistent aug-cc-pVDZ (aVDZ) basis set. Minimal nature of the reported structures is confirmed by doing vibrational frequency run at MP2/aVDZ level of theory using full calculations for n = 1 and 2 and employing grafting based molecular tailoring approach for the n = 4, 6, and 7...
April 21, 2017: Journal of Chemical Physics
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