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Synthesis,spectroscopic characterization,thermal behaviour,in vitro antimicrobial and anticancer activities of novel ruthenium tricarbonyl complexes containing monodentate V‐shaped Schiff bases 下载免费PDF全文
The interaction of Ru3(CO)12 with a novel family of monodentate V‐shaped Schiff base ligands (L1–4; L1: (E)‐1‐(4‐((4‐bromobenzylidene)amino)phenyl)ethanone, L2: (E)‐1‐(3‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L3: (E)‐1‐(4‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L4: (E)‐1‐(3‐(3,4‐dimethoxybenzylideneamino)phenyl)ethanone) in air under atmospheric pressure afforded the novel complexes [Ru(CO)3(L1–4)2]. The parent ligands and their complexes were characterized using elemental analyses and spectroscopic techniques. In addition, the structure of the representative ligand L1 was determined using single‐crystal X‐ray analysis. The stereochemistry and theoretical optimization of the three‐dimensional geometry of the ligands and their complexes were justified. In vitro antimicrobial screening against bacterial stains Escherichia coli and Staphylococcus aureus and fungus Candida albicans was conducted. Cytotoxicity of the compounds as anti‐tumour agents was evaluated against liver carcinoma (HepG2), breast carcinoma (MCF7) and colon carcinoma (HCT‐116) cell lines relative to cisplatin and doxorubicin. The complexes showed variable in vitro cytotoxic activities against the three studied cell lines, with IC50 values less than those of cis‐platin, and thus appear to be building blocks for promising anti‐tumour agents. 相似文献
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An integrated field-portable surface enhanced Raman scattering (SERS) sensing system has been developed and evaluated for quantitative analysis of energetics such as perchlorate (ClO(4)(-)) and trinitrotoluene (TNT) at environmentally relevant concentrations and conditions. The detection system consists of a portable Raman spectrometer equipped with an optical fiber probe that is coupled with novel elevated gold bowtie nanostructural arrays as a sensitive and reproducible SERS substrate. Using the standard addition technique, we show that ClO(4)(-) and TNT can be quantified at concentrations as low as 0.66 mg L(-1) (or ~6.6 μM) and 0.20 mg L(-1) (~0.9 μM), respectively, in groundwater samples collected from selected military sites. This research represents the first step toward the development of a field SERS sensor which may permit rapid, in situ screening and analysis for various applications including national security, chemical, biological and environmental detection. 相似文献
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Nahla A. Hatab Gyula Eres Paul B. Hatzinger Baohua Gu 《Journal of Raman spectroscopy : JRS》2010,41(10):1131-1136
Techniques for rapid and sensitive detection of energetics such as cyclotrimethylenetrinitramine (RDX) are needed both for environmental and security screening applications. Here we report the use of surface‐enhanced Raman scattering (SERS) spectroscopy to detect traces of RDX with good sensitivity and reproducibility. Using gold (Au) nanoparticles (∼90–100 nm in diameter) as SERS substrates, RDX was detectable at concentrations as low as 0.15 mg/l in a contaminated groundwater sample. This detection limit is about two orders of magnitude lower than those reported previously using SERS techniques. A surface enhancement factor of ∼6 × 104 was obtained. This research further demonstrates the potential for using SERS as a rapid, in situ field screening tool for energetics detection when coupled with a portable Raman spectrometer. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Five types of haemocytes are observed in the fourth larval instar of the black cutworm, Agrotis ipsilon: prohaemocytes (PRs), plasmatocytes (PLs), granulocytes (GRs), spherule cells (SPs) and adipohaemocytes (ADs). Infection of A. ipsilon fourth larval instar with Bacillus thuringiensis and dimilin resulted in a reduction of the total haemocyte count. Changes in the differential haemocyte population during bacterial and dimilin infections have been assessed. The PRs % decreased significantly while SPs, PLs, and GRs % increased significantly after the application of the two insecticides at 12 and 24 h. Ultrastructural alternations and malformations have been observed in circulating haemocytes of A. ipsilon larvae treated with dimilin and B. thuringiensis. 相似文献
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International Journal of Theoretical Physics - The interaction between two modes quantized field and asymmetric two atoms represents one of the important quantum models to study the nonclassical... 相似文献
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The purpose of this note is to investigate the stabilization of the wave equation with Kelvin–Voigt damping in a bounded domain. Damping is localized via a non-smooth coefficient in a suitable subdomain. We prove a polynomial stability result in any space dimension, provided that the damping region satisfies some geometric conditions. The main novelty of this note is that the geometric situations covered here are richer than that considered in [25], [22], [16] and include in particular an example where the damping region is not localized in a neighborhood of the whole or a part of the boundary. 相似文献
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Farah Noun John Manioudakis Rafik Naccache 《Particle & Particle Systems Characterization》2020,37(8):2000119
Carbon dots possess versatile optical properties that have prompted their investigation in applications including photocatalysis, photovoltaics, imaging, and drug delivery, among others. However, the preparation of these nanodots is accompanied by the formation of fluorophores and intermediates, which can be difficult to separate. In the absence of thorough purification protocols, the reported optical properties are often heterogeneous, which hinders understanding of their physicochemical and optical properties and concrete application development. Here, two hydrophilic carbon dot systems starting with citric acid and diethylenetriamine are prepared. The impact of purification, including dialysis, ultrafiltration, and organic washes, on the properties of the dots is demonstrated. It is shown that monitoring the purification endpoint using near-infrared, fluorescence, and absorbance spectroscopies is possible. Moreover, it is demonstrated that fluorescence quantum yields can be a reliable tool to determine the purification endpoint. This work shows that even carbon dots derived from the same chemical precursors can have different purification profiles and purification requirements. However, the developed approach can be used to determine the proper purification procedure and endpoint for any carbon dot system regardless of the starting materials. Finally, it is envisioned that this work can be easily extended toward the purification of other hydrophilic nanomaterials. 相似文献
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In this article, we highlight generalities about solid propellants (SPs) for space launch. SP is a composition of several ingredients basically oxidizer and reducing materials in order to guarantee the combustion reaction after initialization. SPs require high level control quality analysis methods due to their energetic nature with high probability of auto-inflammation, which presents a serious safety problem, thus, the spectroscopy analysis techniques are required to promote the SPs quality control accuracy. In this article, X ray diffraction (XRD), Fourier transform infrared (FTIR), and near infrared spectroscopy (NIRs) have been introduced as substantial analysis methods on SPs. The main parameters to be determined in the process of the quality control are the crystalline structure using XRD and molecular structure and molecular identification using FTIR. While NIRs combined with chemometrics proved to be a quick and non-destructive analysis tool, it provides concise quantitative data so it has great potential to meet the SPs control quality analysis requirements. 相似文献
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Salama Nahla N. Zaazaa Hala E. Abd El Halim Lobna M. Salem Maissa Y. Abd El Fattah Laila E. 《平面色谱法杂志一现代薄层色谱法》2016,29(3):176-183
JPC – Journal of Planar Chromatography – Modern TLC - A rapid, inexpensive, and stereoselective densitometric—thin-layer chromatographic (TLC) method using l-(+)-tartaric acid and... 相似文献