Có 200+ tài liệu thuộc chủ đề "Journal of Chemistry"
tailieu.vn Xem trực tuyến Tải xuống
In this study, the synthesis of crystalline carbon nitride (CN) was studied via an ionic melt polycondensation of urea precursor in the presence of various salt melts, which were KCl-LiCl, KCl-NaCl, and KCl-ZnCl 2 . While all the salt melts helped to improve the optical properties of the CN, only KCl-LiCl salt melt could form crystalline CN as evidenced by...
tailieu.vn Xem trực tuyến Tải xuống
Electrodeposition of tin(II) from citrate complexes. Vernadskii Institute of General and Inorganic Chemistry of the National Academy of Sciences of Ukraine, Kyiv, Ukraine. Abstract: This paper provides the calculation of the distribution of the concentrations of complex particles of the Sn(II. citrate - water system in the solution volume, on the surface of the electrode, and in the diffusion layer...
tailieu.vn Xem trực tuyến Tải xuống
Comparative study of solvent extraction of molybdenum by various extractants. Abstract: Solvent extraction of molybdenum from various acid media by Alamine 336, Aliquat 336, TOPO, and DEHPA in kerosene was studied. The extraction efficiency of molybdenum by diisobutyl ketone (DIBK), the effects of various parameters like diluents, mineral acids, extractant concentration, and applications of these extractants on molybdenum extraction contained...
tailieu.vn Xem trực tuyến Tải xuống
Preparation and physicochemical characterization of zinc oxide/sodium cellulose composite for food packaging. Abstract: Zinc oxide/sodium cellulose composite with different ZnO loadings was prepared for the first time. The crystal structures of cellulose, sodium cellulose, and ZnO/sodium cellulose composite were characterized by FT-IR, XRD, XPS, SEM, and EDX. ZnO/sodium cellulose showed a similar XRD pattern to that of cellulose II. The...
tailieu.vn Xem trực tuyến Tải xuống
The second step was Pt loading during reduction and deposition into the aqueous suspension of the bifunctional mesoporous silica synthesized by an aqueous solution of formaldehyde as the reducing agent. The adsorption properties and thermodynamic parameters of the bifunctional mesoporous silica synthesized to adsorb Zn(II) ions were studied. The effects of pH, initial concentration, temperature, adsorption equilibrium, and adsorption kinetics...
tailieu.vn Xem trực tuyến Tải xuống
Naphthoxazoles and heterobenzoxazoles: cholinesterase inhibition and antioxidant activity. In this study we evaluated cholinesterase inhibitory and antioxidant activity of seven oxazole derivatives. They have also been tested for antioxidant activity, but never for cholinesterase inhibitory activity. Among the tested oxazole derivatives, fused heterobenzoxazole compounds with pyridine and thiophene moi- ety, oxazolo[5,4- h ]isoquinoline, thieno[2’,3’:5,6]benzo[1,2-d ]oxazole, and thieno[3’,2’:5,6]benzo[1,2-d ]oxazole, showed the...
tailieu.vn Xem trực tuyến Tải xuống
Novel “turn off-on” sensors for detection of DNA-acrylamide interaction using ZnS quantum dots as a phosphorescent probe. In the “turn-off” mode, ACR was absorbed onto the surface of QDs via electrostatic interaction, which caused a quenching effect of room-temperature phosphorescence signal by photoinduced electron-transfer mechanism. ACR was removed from the QDs’ surface with the addition of DNA. The major formation...
tailieu.vn Xem trực tuyến Tải xuống
The effect of blend ratios (PVA/CS and 7% (w/w. SEM images indicated that more flat nanofibers were synthesized at lower flow rates, but the shape of the fibers was more circular at higher flow rates. On the other hand, an increase in CS ratio, flow rate, and applied voltage caused a decrease in the transmittance values of the fibers while...
tailieu.vn Xem trực tuyến Tải xuống
Abstract: An efficient and facile method has been developed for the synthesis of alkyl bromides from various alcohols under mild conditions using a triphenylphosphine (PPh 3 ) /1,2-dibromotetrachloroethane (DBTCE) complex in excellent yields and very short time (5 min). 1 Alkyl bromides are often used in synthetic organic chemistry because they can be easily prepared using many reagents. For this...
tailieu.vn Xem trực tuyến Tải xuống
Two of the synthesized compounds are exceptional because they are first of this type that demonstrate concentration-dependent antifungal in vitro activity against two species of the genus Candida in minimal YNB-SG medium. Studies show that dietary nucleotides and nucleosides may be important for proper functioning of the immune system, small intestinal growth and development, lipid metabolism, and hepatic function. 4...
tailieu.vn Xem trực tuyến Tải xuống
Plasma O 2 modifies the structure of synthetic zeolite-A to improve the removal of cadmium ions from aqueous solutions. Abstract: The present study addresses the removal of cadmium ions (Cd(II)) from aqueous solutions at a pH of 7.5 using zeolite-A activated by exposure to oxygen plasma. Infrared-attenuated total reflectance spectroscopy, X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy were...
tailieu.vn Xem trực tuyến Tải xuống
Crystal structure and Hirshfeld surface analysis of 1,2-ethylene-bis (para-methyl pyridinium) dichromate as a new selective and mild agent in oxidation of alcohols. is used as a new oxidizing agent in conversion of some alcohols to their corresponding carbonyl compounds in CH 3 CN solvent and also under solvent-free conditions. However, a much shorter reaction time is achieved in solvent-free conditions....
tailieu.vn Xem trực tuyến Tải xuống
Abstract: In the current study, four new phenolic oxime ligands (HL1ox–HL4ox) containing diazo groups (-N =N-) were synthesized and used for liquid-liquid extraction of heavy metal ions [Cu(II), Ni(II), and Zn(II. Hirshfeld surface analysis of the compounds was performed to determine the contribution of different intermolecular contacts to the stability of the structures. The effects of the substitute groups (at...
tailieu.vn Xem trực tuyến Tải xuống
Phosphoric acid was added dropwise to each suspension to obtain HAP/HPAM-n composites. HPAM amount in the composite affects the retention of methylene blue (MB) dye.. The result shows that the increase of HPAM in the material leads to the increase of the dye retention capacity. We deduce in this work that the composite HAP/HPAM-75 is a good candidate for MB...
tailieu.vn Xem trực tuyến Tải xuống
doi:10.3906/kim-1807-54 h t t p. Abstract: The complexes of peripherally tetra-substituted metal-free (8), lead(II) (9), and zinc(II) (10) phthalocyanine derivatives were synthesized for the first time in this work. The thermogravimetric behavior of compounds 8–10 was determined by thermogravimetric analysis method in addition to these spectral methods.. 1 Because these chemicals have a large π- conjugated system, they absorb strongly...
tailieu.vn Xem trực tuyến Tải xuống
Rapid and on-site electrochemical detection of bisphenol A and arsenic in drinking water using a novel electrode array. Abstract: The paper describes a novel dip-and-gauge hand-held sensor device for the rapid, cost-effective, and on-site detection of bisphenol A and arsenic in drinking water samples. The sensor was employed for the chronoamperometric detection of bisphenol A and voltammetric determination of arsenic...
tailieu.vn Xem trực tuyến Tải xuống
Investigation of the structural and physicochemical requirements of quinoline-arylamidine hybrids for the growth inhibition of K562 and Raji. The QSAR models revealed important physicochemical and structural requirements for the antitumor activity: enhanced 3D molecular distribution of mass calculated at radius 11 Å from the center of molecule, a higher number of terminal electronegative atoms, extension of the molecules’ central linker...
tailieu.vn Xem trực tuyến Tải xuống
high sensitivity and selectivity were recorded for Fe 3+ by naked eye and UV-Vis spectra in DMF-aqueous HEPES buffer (v:v, 1:1, pH 6.8). sensed Cu 2+ and Al 3+ ions selectively by UV-Vis spectra. L 1 sensitively responded to anions according the order of OH − >C 2 O 2 4 − >F − in the 1:1 mixture and OH...
tailieu.vn Xem trực tuyến Tải xuống
3D-QSAR/HQSAR-based analysis of bioconcentration and molecular modification of monophenyl aromatic compounds. Logarithms of experimental bioconcentration data (logBCF) were used as dependent variables and the physicochemical properties of the aromatic compound congeners were used as independent variables. Furthermore, the molecular holographic quanti- tative structure–activity relationship (HQSAR) model constructed by the HQSAR module in Sybyl software was used to establish a method...
tailieu.vn Xem trực tuyến Tải xuống
The prepared particles can be controlled by using an external magnetic field, which makes them very promising candidates in biological applications and Raman spectroscopic analysis of dissolved organic species. The magnetic property of the prepared particles lowers the detection limits through preconcentration with solid-phase extraction in SERS analysis. The performance of the prepared nanostructures was evaluated as a SERS substrate...