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1.
A supersymmetric technique for the bound-state solutions of the s-wave Klein-Gordon equation with equal scalar and vector standard Eckart-type potential is proposed. Its exact solutions are obtained. Possible generalization of our approach is outlined.  相似文献   
2.
Two Novel long chain fatty acids, (5Z, 9Z)-6-bromo-25-methyl-5,9-hexacosadienoic and (5Z, 9Z)-6-bromo-24-methyl-5,9-hexacosadienoic acids were found in the phospholipids of Petrosiaficiformis and P.hebes. Their structures were elucidated with the help of CI-EI7MS and a homogeneous hydrogenation catalyst.  相似文献   
3.
4.
Abstract

A series of novel β-mercapto carbonyl compounds (3a–z), methyl 2-(3-oxo-1,3-diarylpropylthio)acetate, were synthesized and characterized via iodine-catalyzed addition of methyl thioglycolate to chalcones (1a–z).

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   
5.
People drink various types of tea without knowing the side effects of biological and chemical contents and radiopharmaceutical interactions. In current study, it is aimed to evaluate the effects of green tea extract in different extraction solvents on the radiolabeling of the blood constituents with 99mTc and on the biodistribution of radiopharmaceutical sodium pertechnetate (Na99mTcO4) in male Wistar Albino rats. The extraction of green tea was performed in different solvents. Biodistribution studies were performed on male rats which were treated via gavage with green tea extract in different extraction solvents or saline (0.9 % NaCl) as a control group for 7 days. The radiolabeling of blood constituents performed incubating with SnCl2 and 99mTc. According to experimental results, radiolabeling blood components with 99mTc were not modified in the usage of the different extraction solvents for green tea extraction, but a significant alteration (P < 0.05) of biodistribution of Na99mTcO4 was observed after treatment with green tea extract in distilled water. Although there is no considerable effect on radiolabeling of blood components, there is an outstanding change on the biodistribution studies especially with green tea extract in distilled water. The identified change monitored in this study may cause to reduce the risk of misdiagnosis and/or avoid the repetition of the examinations in nuclear medicine.  相似文献   
6.
This paper describes a novel approach to detect Cd(II) using the combination of the differential pulse anodic stripping voltammetry and magnetic nanoparticle based dispersive solid phase microextraction as an efficient, green and accurate method. Currents of Cd(II) increased linearly in the range from 75 to 2000 ng L−1 Cd(II) with a detection limit of 21.6 ng L−1. The RSD values of 2.6 and 6.0 % for 1.00 and 0.10 μg L−1 respectively showed that proposed method has an acceptable repeatability. Recovery values between 92.3 and 98.6 % showed that this approach can be successfully used for determination of Cd(II) in water samples.  相似文献   
7.
A voltammetric study of the oxidation of Ceftazidime (CEFT) has been carried out at the glassy carbon electrode by cyclic, differential pulse (DPV) and square wave (SWV) voltammetry. The oxidation of CEFT was irreversible and exhibited diffusion controlled process depending on pH. The oxidation mechanism was proposed and discussed. According to the linear relationship between the peak current and concentration, DPV and SWV voltammetric methods for CEFT assay in pharmaceutical dosage forms and human urine were developed. For analytical purposes, a well resolved diffusion controlled voltammetric peak was obtained in 0.1 M H2SO4 at 1.00 and 1.02 V for differential pulse and square wave voltammetric techniques, respectively. The linear response was obtained within the range of 4 × 10?6?8 × 10?5 M with a detection limit of 6 × 10?7 M for differential pulse and 4 × 10?6–2 × 10?4 M with a detection limit of 1 × 10?6 M for square wave voltammetric technique. The determination of CEFT in 0.1 M H2SO4 was possible over the 2 × 10?6–1 × 10?4 M range in urine sample for both techniques. The standard addition method was used for the recovery studies.  相似文献   
8.
In this study, the effects of ultrasound on ozone treatment processes for bleaching cotton fabrics were investigated and compared with the conventional hydrogen peroxide bleaching process (60 °C over 90 min). Two ultrasonic + ozone treatments of cotton fabric samples were carried out: (1) ozone in an ultrasonic homogenizer (UH) and (2) ozone in an ultrasonic bath. Ozone dosages, temperature and time variations were determined with both ozone-ultrasonic bleaching processes. Whiteness, yellowness, weight, tensile strength properties, FTIR (ATR) spectra and visual appearance, via scanning electron microscopy of treated cotton fabrics as well as chemical oxygen demand (COD) of bleaching effluents, were investigated. It was concluded that the ozone + UH process, conducted for 30 min at 30 °C, produced closely equivalent values of cotton fabric whiteness and yellowness to the classic peroxide bleaching process, with slightly less weight loss, dramatically less COD in the process effluent (29 mg/l for ozone-UH vs. 4,316 mg/l for classical peroxide treatment), and without causing any adverse and/or detrimental effects on loss of fabric strength or elongation of the cotton fabrics. The ozone-UH process also leads to time and energy savings with much less environmental impact. Consequently, the combination of ozonation plus UH carried out at 30 °C over 30 min can be used successfully for cotton bleaching instead of the classic hydrogen peroxide bleaching process.  相似文献   
9.
An electrochemical dsDNA nanobiosensor was fabricated using amino‐functionalized multi walled carbon nanotubes modified glassy carbon electrode (NH2fMWCNTs/GCE) for the sensitive detection of DNA bases and electrochemical monitoring of drug‐DNA interaction. The influence of functional groups on MWCNT was studied by MWCNT functionalized with NH2 (NH2fMWCNTs) and COOH (COOHfMWCNT) groups based on the signal of DNA bases. The modified electrodes were characterized by scanning electron microscopy. One layer of calf thymus double stranded deoxyribonucleic acid (ct‐dsDNA) was immobilized onto the NH2fMWCNTs/GCE (dsDNA/NH2fMWCNTs/GCE). The dsDNA/NH2fMWCNTs/GCE were used to investigate the interaction between the dsDNA and the anticancer drug gemcitabine by differential pulse voltammetry in acetate buffer of pH 4.70. For the confirmation of interaction, the lowering in intensity of the current signals of guanine and adenine was considered as an indicator. Electrochemical impedance spectroscopy studies were performed for the comparison of the modified surfaces. In order to define and visualize the interaction mechanism between gemcitabine and dsDNA/NH2fMWCNTs/GCE at the molecular level, in silico methods including docking and molecular dynamics simulations were employed.  相似文献   
10.
Phenoxy- and naphthoxy-substituted bisphenol-bridged cyclic phosphazenes were synthesized in 2 steps and their thermal, photophysical, and electrochemical properties were investigated. The structures of the cyclic phosphazene compounds were determined by ESI-MS mass spectrometry and 1 H, 13 C, and 31 P NMR spectroscopies. The photophysical studies of phenoxy- and naphthoxy-substituted bridged cyclophosphazenes were investigated by means of absorption and fluorescence spectroscopies in different solvents. Thermal and electrochemical properties of the target compounds were also studied. Furthermore, the excimer emissions through intramolecular interactions in solution and in solid state were investigated by fluorescence spectroscopy and the theoretical calculations were performed in detail using DFT.  相似文献   
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