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In this study, we fabricated an effective and sensitive DNA biosensor based on flower-like Pt/NiCo2O4 modified carbon paste electrode (FL-Pt/NiCo2O4/CPE) for detection of pramipexole (PPX). Spectrophotometry, differential pulse voltammetry (DPV) and docking methods were employed to evaluate the interaction of DNA-PPX. Moreover, the DPV technique was chosen to monitor the electrochemical response of guanine on the DNA biosensor. The relationship between the concentration of PPX and the oxidation signal of guanine was linear in the range of 0.4 to 310.0 μM and a limit of detection (LOD) of 0.09 μM was calculated. 相似文献
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Russian Journal of Electrochemistry - In this paper, the use of a screen printed electrode modified by feather like La3+/ZnO nano-flowers for the determination of sertraline was described. These... 相似文献
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Host–Guest Assembly of a Molecular Reporter with Chiral Cyanohydrins for Assignment of Absolute Stereochemistry 下载免费PDF全文
Hadi Gholami Dr. Mercy Anyika Jun Zhang Dr. Chrysoula Vasileiou Prof. Dr. Babak Borhan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9235-9239
The absolute stereochemistry of cyanohydrins, derived from ketones and aldehydes, is obtained routinely, in a microscale and derivatization‐free manner, upon their complexation with Zn‐MAPOL, a zincated porphyrin host with a binding pocket comprised of a biphenol core. The host–guest complex leads to observable exciton‐coupled circular dichroism (ECCD), the sign of which is easily correlated to the absolute stereochemistry of the bound cyanohydrin. A working model, based on the ECCD signal of cyanohydrins with known configuration, is proposed. 相似文献
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Today, analyzing of sound pressure level and frequency is considered as an important index in human society. Sound experts believe that analyzing of these parameters can help us to better understanding of work environments. Sound measurements and frequency analysis did to fix the harmful frequency in all sections in Shiraz gas power plant with sound analyzer model BSWA 308. The sound pressure levels (LP) and the one and one-third octave band were continuously measured in A and C weighting networks and slow mode for time response. Excel 2013 and Minitab 18.1 software used for statistical calculations. Results analyzed by Minitab 18.1 software. The highest harmful frequency in Shiraz Gas Power Plant (SGPP) was 50 Hz with 115 dB. The sound pressure level (SPL) ranged from 45 dB to 120 dB in one-third octave band and weighting network C. The maximum sound pressure level was in Craft electricity generator with 105.3 dB and 67 Hz. Sound pressure level in surrounded environment was 120 dB. According to the results, in this industry the sound pressure level exceeded the Occupational Exposure Level of Iran (OEL). The value of sound pressure level were higher than the Standard of occupational health. SGPP consumes 47000 cubic meters of natural gas per hour to produce 100 MW (Mega Watt) of electricity. It is very high and it is not economical and cost effective. These numbers indicate that the power plant’s efficiency is low. It could be concluded that the noise pollution is an important issue in these industries. Moreover, SGPP produce noise with loss energy. Frequencies rotation at high sound pressure levels toward low frequencies were happened. 相似文献
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More than 70% of the world's nickel reserves are found in laterite ores. In this research, a laterite ore sample, containing Ni, Co, and Fe, was employed to study the recovery of nickel and cobalt. Thus, the effect of calcination, acid concentration, percent solids, and stirring rate on nickel and cobalt recoveries from an iron-rich laterite sample was investigated. Optimization with response surface methodology and kinetic studies were performed. The calcination of the sample prior to leaching at 500°C for 2 h provided condition for better nickel and cobalt dissolutions. At optimal conditions, the concentration of sulfuric acid, solid-to-liquid ratio, stirring speed, temperature, and time test were equal to 5 M, 0.1, 370 rpm, 90°C, and 2 h, respectively. The highest recoveries of nickel and cobalt were 65.9% and 63.1%, respectively. Solids content had a negative effect on Ni and Co recovery, whereas acid concentration was positively affected. Addition of 10% (w/v) NaCl in the presence of 5 M acid concentration, 60°C, 370 rpm, and leaching time of 2 h increased the nickel and cobalt recoveries, 15.3% and 21.4%, respectively. The high dependence of process on temperature indicates chemical control; the activation energies Ea = 59.54 and Ea = 45.74 kJ/mol, respectively, for nickel and cobalt, were also consistent with this conclusion. 相似文献
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Nanomolar Determination of Methyldopa in the Presence of Large Amounts of Hydrochlorothiazide Using a Carbon Paste Electrode Modified with Graphene Oxide Nanosheets and 3‐(4′‐Amino‐3′‐hydroxy‐biphenyl‐4‐yl)‐acrylic Acid 下载免费PDF全文
A novel electrochemical sensor for sensitive detection of methyldopa at physiological pH was developed by the bulk modification of carbon paste electrode (CPE) with graphene oxide nanosheets and 3‐(4′‐amino‐3′‐hydroxy‐biphenyl‐4‐yl)‐acrylic acid (3,′AA). Applying square wave voltammetry (SWV), in phosphate buffer solution (PBS) of pH 7.0, the oxidation current increased linearly with two concentration intervals of methyldopa, one is 1.0×10?8–1.0×10?6 M and the other is 1.0×10?6–4.5×10?5 M. The detection limit (3σ) obtained by SWV was 9.0 nM. The modified electrode was successfully applied for simultaneous determination of methyldopa and hydrochlorothiazide. Finally, the proposed method was applied to the determination of methyldopa and hydrochlorothiazide in some real samples. 相似文献
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Mahdi Mirzaei Hossein Eshghi Mohammad Rahimizadeh Mehdi Bakavoli Maryam M. Matin Minoo Hosseinymehr Hadi Amiri Rudbari Giuseppe Bruno 《中国化学会会志》2015,62(12):1087-1096
A series of α‐aminophosphonates were synthesized through one‐pot condensation of aryl aldehydes, aryl amines and diethyl phosphite in the absence of any catalyst and organic solvents. All the synthesized α‐aminophosphonates were characterized by spectral and elemental analysis and in the case of compound 4j by X‐ray crystallography. Some of these new α‐aminophosphonate derivatives were found to have cytotoxic activity on the cancer cell line DU145 in vitro by the MTT method. 相似文献
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Hadi Minbashian Hojatolah Adibi Mehdi Dehghan 《Numerical Methods for Partial Differential Equations》2017,33(6):2062-2089
This article concerns with incorporating wavelet bases into existing streamline upwind Petrov‐Galerkin (SUPG) methods for the numerical solution of nonlinear hyperbolic conservation laws which are known to develop shock solutions. Here, we utilize an SUPG formulation using continuous Galerkin in space and discontinuous Galerkin in time. The main motivation for such a combination is that these methods have good stability properties thanks to adding diffusion in the direction of streamlines. But they are more expensive than explicit semidiscrete methods as they have to use space‐time formulations. Using wavelet bases we maintain the stability properties of SUPG methods while we reduce the cost of these methods significantly through natural adaptivity of wavelet expansions. In addition, wavelet bases have a hierarchical structure. We use this property to numerically investigate the hierarchical addition of an artificial diffusion for further stabilization in spirit of spectral diffusion. Furthermore, we add the hierarchical diffusion only in the vicinity of discontinuities using the feature of wavelet bases in detection of location of discontinuities. Also, we again use the last feature of the wavelet bases to perform a postprocessing using a denosing technique based on a minimization formulation to reduce Gibbs oscillations near discontinuities while keeping other regions intact. Finally, we show the performance of the proposed combination through some numerical examples including Burgers’, transport, and wave equations as well as systems of shallow water equations.© 2017 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 2062–2089, 2017 相似文献