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A variety of novel thiazolo/oxazolo pyridine derivatives were synthesized via an efficient, one-pot, multi-component reaction of enamines derived from the addition of cysteamine hydrochloride/ethanolamine to 1,1-bis(methylthio)-2-nitroethene with aromatic aldehydes and cyanoacetohydrazide in the presence of catalytic amount of Et3N. This reaction includes some important aspects like simple operation under mild conditions, high atom economy, easy accessibility of reactants, simple workup procedure, and the use of EtOH/H2O as a green reaction medium. 相似文献
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Development of highly active photocatalysts for treatment of dye-laden wastewaters is vital. The photocatalytic removal of azo dye Reactive Black 5 was investigated by Fe3O4-WO3-3-aminopropyltriethoxysilane (APTES) nanoparticles in the presence of visible light. The Fe3O4-WO3-APTES nanoparticles were synthesized via a facile coprecipitation method. The photocatalyst was characterized by XRD, FT-IR, SEM, EDX, VSM, UV–Vis, and pHPZC techniques. The effects of some operational parameters such as solution pH, nanophotocatalyst dosage, initial RB5 concentration, H2O2 concentration, different purging gases, and type of organic compounds on the removal efficiency were studied by the Fe3O4-WO3-APTES nanoparticles as a photocatalyst. Maximum phtocatalytic activity was obtained at pH 3. The photocatalytic removal of RB5 increased with increasing H2O2 concentration up to 5?mM. The removal efficiency declined in the presence of different purging gases and all types of organic compounds. First-order rate constant (kobs) decreased from 0.027 to 0.0022?min?1 and electrical energy per order (EEo) increased from 21.33 to 261.82 (kWh/m3) with increasing RB5 concentration from 10 to 100?mg/L, respectively. The efficiency of LED/Fe3O4-WO3-APTES process for RB5 removal was approximately 89.9%, which was more effective than the LED/Fe3O4-WO3 process (60.72%). Also, photocatalytic activity decreased after five successive cycles. 相似文献
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Bradley T. Falk Yingkai Liang Marc Bailly Fahimeh Raoufi Ahmet Kekec Dmitri Pissarnitski Dennis Feng Lin Yan Songnian Lin Laurence Fayadat-Dilman Dr. Mark A. McCoy 《Chembiochem : a European journal of chemical biology》2020,21(3):315-319
NMR measurements of rotational and translational diffusion are used to characterize the solution behavior of a wide variety of therapeutic proteins and peptides. The timescales of motions sampled in these experiments reveal complicated intrinsic solution behavior such as flexibility, that is central to function, as well as self-interactions, stress-induced conformational changes and other critical attributes that can be discovery and development liabilities. Trends from proton transverse relaxation (R2) and hydrodynamic radius (Rh) are correlated and used to identify and differentiate intermolecular from intramolecular interactions. In this study, peptide behavior is consistent with complicated multimer self-assembly, while multi-domain protein behavior is dominated by intramolecular interactions. These observations are supplemented by simulations that include effects from slow transient interactions and rapid internal motions. R2–Rh correlations provide a means to profile protein motions as well as interactions. The approach is completely general and can be applied to therapeutic and target protein characterization. 相似文献
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The problems with non-degradable materials in different applications have led to an interest in materials based on bionanocomposites. In this study, polymer–montmorillonite nanocomposites based on natural polymers (chitosan, alginate, gelatin and starch) and montmorillonite (MMT) were prepared using solution intercalation method. Then hybrid nanocomposites were synthesized by chemical oxidative polymerization of aniline in the presence of polymer–MMT nanocomposites. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy (TEM) and thermogravimetric analysis (TGA) were employed to characterize the nanocomposites. FT-IR confirmed the successful preparation of hybrid nanocomposites. From the XRD results, intercalation of the MMT platelets in the matrix of polymers was examined. Further investigation by TEM images showed a mixed intercalated and flocculated structure for nanocomposites. Moreover, the TGA results showed improved thermal stability for the nanocomposites. The results presented in this study showed the feasibility of using these hybrid nanocomposites with improved properties in wide range of applications. 相似文献
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Optimization of multiplex PCR for the identification of animal species using mitochondrial genes in sausages 总被引:1,自引:0,他引:1
Fahimeh Parchami Nejad Farzaneh Tafvizi Maryam Tajabadi Ebrahimi Seyed Ebrahim Hosseni 《European Food Research and Technology》2014,239(3):533-541
Detection of species fraud in meat products is very important in order to protect consumers from undesirable adulteration, as well as for the economic, religious and health aspects. The most important reason for verification of the labeling statements is to detect fraudulent substitution of expensive meat components with other cheaper animals or mislabeling. The aim of this study was to develop a multiplex PCR that could be used in the simultaneous identification of multiple meat species. In this study, ten sausages with a minimum beef content of 55 %, from ten different manufacturing companies, and five samples of cow, chicken, goat, camel and donkey raw meats, for the purpose of positive control, were collected from food markets in Tehran, Iran. Total DNA was extracted from each sausage and the raw meats. Primers were selected in different regions of mitochondrial DNA (12S rRNA, cytochrome b and NADH dehydrogenase subunits 2) for identification of meat species. 12S rRNA and NADH dehydrogenase subunits 2 primers generated specific fragments of 183 and 145 bp length, for chicken and donkey, respectively. Three different specific primers were used for amplification of cytochrome b gene in goat, camel and cattle species and amplified species-specific DNA fragments of 157, 200 and 274 bp, respectively. The results proved that half of the specimens were contaminated with chicken meat, and this was greater than the proportion of beef stated on the label, while the other half only had chicken residuals, and no beef content. No contamination was found with goat, donkey or camel meats. These findings showed that molecular methods, such as multiplex PCR, is a potentially reliable, sensitive and accurate assay for the detection of adulterated meat species in mixed meat products. 相似文献
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Nasser Arsalani Fahimeh Kazeminava Ali Akbari Hamed Hamishehkar Esmaiel Jabbari Hossein S Kafil 《Polymer International》2019,68(4):667-674
The synthesis is reported of novel hybrid hydrogels based on ethylenediaminetetraacetic acid dianhydride and poly(ethylene glycol) (PEG) with octa‐aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA‐POSS) as a nano‐crosslinker under solvent‐free conditions. The molecular weight of PEG was varied between 600 and 1000 Da. The synthesized hydrogels were characterized using various techniques. Further, the swelling behavior and antibacterial activity of the hydrogels and release kinetics of metronidazole (MTZ) as a model drug from them were evaluated. Experimental results demonstrate that hydrogels with tunable properties can be synthesized by varying the PEG molecular weight and type of crosslinker (hybrid or organic). Among the synthesized hybrid hydrogels, that crosslinked by OA‐POSS with long PEG chains (1000 Da) showed the highest swelling degree (2000%), drug encapsulation efficiency (88%) and extent of MTZ release (96%). © 2018 Society of Chemical Industry 相似文献