Có 180+ tài liệu thuộc chủ đề "Journal of Chemistry"
tailieu.vn Xem trực tuyến Tải xuống
Exploring inhibition of chemiluminescence mechanisms with fluorescence quenching studies and interaction energy calculations. The capacity to inhibit the CL of three carbamates is in the order of carbaryl (CBL) >carbofuran (CBF). Mechanisms of carbamates inhibiting SCC-luminol-H 2 O 2 CL are investigated using fluorescence quenching and quantum chemistry simulations for the first time in this work. Carbamate-SCC interactions studied using...
tailieu.vn Xem trực tuyến Tải xuống
Quantum chemical calculations and conformational analyses of the compounds were carried out at HF/6-31G* level.. As a result of the comparison of the matrices that are called electron conformational submatrices of activity, the pharmacophoric group of the compounds responsible for the activity was found at the determined tolerance intervals. Validation of the 4D-QSAR model was appraised by the leave-one-out cross-validation...
tailieu.vn Xem trực tuyến Tải xuống
Mannich bases.. 1-(Furan-2-yl)-3-morpholinopropan-1-one hydrochloride (1b): White solid. (E)-5-Morpholino-1-phenylpent-1-en-3-one hydrochloride (1f): White solid. 3-(1H -Indol-3-yl)-1-phenylpropan-1-one (4a): White solid. 1 H NMR (400 MHz, DMSO) δ 3.04 (t, J = 7.4 Hz, 2H), 3.42 (t,. J = 7.4 Hz, 2H), 6.97 (t, J = 7.4 Hz, 1H), 7.06 (t, J = 7.0 Hz, 1H), 7.16 (bs, 1H), 7.32 (d, J = 8.0...
tailieu.vn Xem trực tuyến Tải xuống
Metal nanoparticles/carbon nanotube modified electrodes for voltammetric determination of boron. Abstract: This study describes a sensitive and accurate voltammetric method for determination of boron using metal nanoparticles/carbon nanotube modified electrodes. The oxidation peak of Alizarin Red S (ARS) at –0.59 V in the boron- ARS complex formed in ammonium/ammonia buffer solution (pH 8.5) was evaluated as a response. The characteristics...
tailieu.vn Xem trực tuyến Tải xuống
which was found as a pair of two doublets at δ H J = 17.4 and 17.7 Hz), and also the presence of two singlets at δ H 5.68–5.77 due to the H-5 proton and two broad D 2 O-exchangeable singlets at δ H. 4.57 (d, 1H, H 2 , J = 16.2 Hz), 4.72 (d, 1H, H 2 ,...
tailieu.vn Xem trực tuyến Tải xuống
The catalyst loaded with 2 wt.% manganese on desilicated HZSM-5 demonstrated the best catalytic performance in terms of the highest selectivity of C = 2 to C = 4 olefins (about 93%) and about 52% selectivity of propylene at near 99% methanol conversion in the MTP reaction for a long operation (264 h). 4,5 On account of the increasing market...
tailieu.vn Xem trực tuyến Tải xuống
Please see the Supplementary data for spectra of the compounds.. Furthermore, its 1 H NMR showed a quartet of two protons at δ 4.25 and a triplet for three protons at δ 1.28, typical for ethyl ester. Besides this, it also showed peaks at δ 8.06 as a doublet for one proton, at δ 7.52–7.46 as a multiplet for two...
tailieu.vn Xem trực tuyến Tải xuống
Neutral atoms and ion energies, accurate ionization potential, and electron affinities by polynomial generator coordinate Hartree–Fock method. Abstract: We have developed accurate Gaussian basis functions obtained with the polynomial generator coordinate Hartree–Fock (p-GCHF) method for H, Zn, and Ga-Kr atoms. These basis sets have been applied in the calculation of nonrelativistic energies for neutral atoms, monovalent cations, monovalent anions, ionization...
tailieu.vn Xem trực tuyến Tải xuống
Novel optical sensor-based method for determining total tocopherol content in serum. In this study, a novel optical sensor-based method was proposed for determining total tocopherol content (TTC) of serum, with selectivity for α -tocopherol over β -carotene. The proposed method is based on the use of a copper(II)-neocuproine complex (Cu(II)-Nc) reagent immobilized onto a Nafion membrane, and the absorbance changes...
tailieu.vn Xem trực tuyến Tải xuống
Quantification of flavonoids isolated from Mentha spicata in selected clones of Turkish mint landraces. The solvent was removed under reduced pressure to yield the extract, subjected to silica gel column chromatography to isolate 5-demethyl sinensetin (1), hesperidin (2), didymin (3), and linarin (4), the structures of which were elucidated by 1D NMR, 2D NMR, and LC-TOF/MS. The isolated compounds were...
tailieu.vn Xem trực tuyến Tải xuống
0 Br CH 2 CH 2 CH 2 C 6 H 5 1 Br CH 2 CH 2 CH 2 C 6 H 5 2 Br CH 2 CH 2 CH 2 C 6 H 5 1f. Br CH 2 CH 2 CH 2 C 6 H 5 H I CH 2 CH 3 H Br CH 2 CH 2...
tailieu.vn Xem trực tuyến Tải xuống
The adsorption capacity of the produced AC towards phenol was measured and, after only 30 min, the removal percentage reached over 95%. The greatest affinity towards phenol was obtained at pH of 4 justified by the pH pzc of the sorbent and speciation of phenol in solution. The final cost of adsorbents is one of the key challenges in using...
tailieu.vn Xem trực tuyến Tải xuống
Voltammetric determination of glycopyrrolate in a pharmaceutical formulation. Abstract: The electrochemical activity of glycopyrrolate was studied. CV indicated that glycopyrrolate has a reversible redox reaction on the working electrode surface, with an anodic peak current at approximately 1.05 V and a cathodic peak at 0.80 V. Several parameters that affect the sensitivity of these methods were optimized for the quantitation...
tailieu.vn Xem trực tuyến Tải xuống
Preparation of self-propelled Cu-Pt micromotors and their application in miRNA monitoring. Catalytic micromotors are strongly influenced by the presence and concentration of specific ions and chemicals in the environment, making them useful as sensors and actuators. In this work, copper (Cu)-platinum (Pt) micromotors were fabricated by using the magnetron sputtering method for the first time in the literature and their...
tailieu.vn Xem trực tuyến Tải xuống
Determination of hydrogen peroxide with an enzymeless amperometric sensor based on poly(vinylferrocene)-supported Ag nanoparticles. Abstract: An enzymeless electrochemical sensor for detection of low amounts of H 2 O 2 with the aid of Ag nanoparticles supported on conducting poly(vinylferrocene) (PVF) film was developed. Experimental results revealed that contribution of Ag nanoparticles led to remarkable improvement by means of reduction potential...
tailieu.vn Xem trực tuyến Tải xuống
Abstract: NH 3 adsorption and desorption behavior of a commercial Cu-chabazite (CHA) NH 3 selective catalytic reduction (NH 3 -SCR) catalyst was studied in the presence and absence of H 2 O. NH 3 uptake values at various adsorption temperatures were obtained during various steps of the adsorption and temperature-programmed desorption (TPD) experiments. Total NH 3 uptake decreased from 4.6...
tailieu.vn Xem trực tuyến Tải xuống
Compound 14 (Figure 2) exhibited prominent activity against the HTB26 and MCF7 cell lines, having IC 50 values of 14 µM for both. The anticancer activity of the dendrimers was evaluated and significant efficacy was observed for piperazine-terminated organo-iron dendrimers against HTB26 and MCF7 cancer cell lines with IC 50 values of 3.6 µM and 2.5 µM, respectively. The cytotoxicity...
tailieu.vn Xem trực tuyến Tải xuống
Catalytic hydrogenation of furfural and furfuryl alcohol to fuel additives and value-added chemicals. Abstract: The selective hydrogenation of furfural and furfuryl alcohol at different temperatures has been studied using several catalysts. We have shown that Pd/TiO 2 catalysts can be very effective for the synthesis of 2-methylfuran at room temperature. Although adding Ru to the Pd/TiO 2. catalyst contributed to...
tailieu.vn Xem trực tuyến Tải xuống
The aim of this study was to investigate neuroprotective effects of NACA against paraquat (PQ) toxicity in the midbrains of rats by using motor coordination tests and biochemical and histological analysis. The rotarod and accelerod tests were performed prior to and after the experimental period. According to biochemical data, malondialdehyde levels exhibited a significant increase (P <0.05) when the PQ...
tailieu.vn Xem trực tuyến Tải xuống
An evaluation of the adsorption dynamics of phosphate ions onto Fe(II)-montmorillonites. By nitrogen adsorption, the pore size can be obtained in the pore diameter curve with average pore widths of 6.67 nm, 9.96 nm, and 17.07 nm, respectively. The removal rate of phosphate increased rapidly during the first 40 min, in which Fe(II)-MMT (1) and Fe(II)-MMT (2) were stronger adsorption...