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991.
Bloch HA Petersen M Sperotto MM Keşmir C Radzikowski L Jacobsen S Søndergaard I 《Rapid communications in mass spectrometry : RCM》2001,15(6):440-445
Cereal varieties are normally identified using time-consuming methods such as visual examination of either the intact grain or one-dimensional electrophoretic patterns of the grain storage proteins. A fast method for identification of wheat (Triticum aestivum L.) varieties has previously been developed, which combines analysis of alcohol-soluble wheat proteins (gliadins) using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry with neural networks. Here we have applied the same method for the identification of both barley (Hordeum vulgare L.) and rye (Secale cereale L.) varieties. For barley, 95% of the mass spectra were correctly classified. This is an encouraging result, since in earlier experiments only a grouping into subsets of varieties was possible. However, the method was not useful in the classification of rye, due to the strong similarity between mass spectra of different varieties. 相似文献
992.
Nano Fe3O4 particles were obtained in microvawe oven using closed system. Oxovanadium(IV) complexes of Fe3O4@SiO2@(aminomethylphosphine) type ligands were synthesized and characterized using SEM, EDX, TEM, UV‐Visible, XRD, FT‐IR and TG/DTA techniques. Catalytic properties of the synthesized pincer type oxovanadium(IV)‐aminomethylphosphine complexes supported on magnetic nano structure were investigated in the synthesis of 2‐methyl‐1, 4‐naphthoquinone (Vitamin K3, menadione, 2MNQ) from 2‐methyl naphthalene (2MN) in hydrogen peroxide, acetic acid and sulfuric acid. Magnetic‐nano particle supported oxovanadium(IV)‐aminomethylphosphine type complexes were very efficient catalysts with the 51.36‐55.20 % selectivities in conversions of 89.78‐95.01 %. Besides, the hetergeneous complexes were very active in five cycling tests on avarage evaluated in the reusability. 相似文献
993.
A rapid and novel method combining dispersive liquid–liquid microextraction and high-performance liquid chromatography coupled with fluorescence detection was developed for the determination of donepezil in human urine. Parameters affecting extraction efficiency and chromatographic determination, such as the type and volume of the extraction and disperser solvent, pH of sample for dispersive liquid–liquid microextraction, mobile-phase composition, pH, column oven temperature, and flow rate for chromatographic determination, were evaluated and optimized. Using a C18 core–shell column (7.5 × 4.6?mm, 2.7?μm), the determination of donepezil was accomplished within 5?min. Under optimum conditions, developed method was linear in the range of 0.5–25?ng?mL?1 with the correlation coefficient >0.99. Limit of detection was 0.15?ng?mL?1. The relative standard deviation at three concentration levels (2, 12.5, and 20?ng?mL?1) was less than 11% with accuracy in the range of 96.9–102.8%. The results of this study demonstrate that the use of dispersive liquid–liquid microextraction and core–shell column can be considered as a powerful tool for the analysis of donepezil in human urine. 相似文献
994.
Demir Faruk Yenilmez H. Yasemin Koca Atıf Bayır Zehra Altuntaş 《Journal of Solid State Electrochemistry》2022,26(3):761-772
Journal of Solid State Electrochemistry - We report the synthesis of non-peripheral metallophthalocyanines which carry four 4-(4-methoxyphenyl)-2-thiazole-2-thio units. 1H-NMR, FT-IR, UV–Vis,... 相似文献
995.
Gülşah Yilan Mauro Cordella Piergiuseppe Morone 《Current Opinion in Green and Sustainable Chemistry》2022
Green chemistry (GC) was developed to maximise resource efficiency and minimise hazards in chemical processes and products. Over time, the approach evolved into green and sustainable chemistry (GSC), which aims at promoting the development of an ecologically friendly society. GSC encourages society's reliance on sustainable materials and technologies/processes and supports the ambitious sustainability targets set by international organisations. It also steers public attention to the provision of sustainable solutions for producers, consumers and investors. Since GSC implementation requires significant financial investment, this paper describes a broad range of approaches and tools to assess the sustainability of potential investments and shows, although with a primary focus on environmental sustainability, how life cycle approaches could be used to define enhanced key performance indicators. Thus, the paper may serve as a useful reference for: (i) chemical companies interested in evaluating the sustainability performance of activities requiring financial investment, and (ii) investors interested in evaluating the sustainability of potential financial investments. 相似文献
996.
Explosive detection technologies play a critical role in maintaining national security, remain an active research field with many devices and analytical/electroanalytical techniques. Analytical chemistry needs for homeland defense against terrorism make it clear that real-time and on-site detection of explosives and chemical warfare agents (CWAs) are in urgent demand. Thus, current detection techniques for explosives have to be improved in terms of sensitivity and selectivity, opening the way to electrochemical devices suitable to obtain the targeted analytical information in a simpler, cheaper and faster way. For the electrochemical determination of energetic substances, a large number of sensor electrodes have been presented in literature using different modification materials, especially displaying higher selectivity with molecularly imprinted polymers (MIPs). MIPs have already been utilized for the detection of hazardous materials due to their mechanical strength, flexibility, long-time storage and low cost. The sensitivity of MIP-based electrosensors can be enhanced by coupling with nanomaterials such as graphene oxide (GOx), carbon nanotubes (CNTs), or nanoparticles (NPs). Specific characteristics of involved nanomaterials, their modification, detection mechanism, and other analytical aspects are discussed in detail. Non-MIP electrosensors are generally functionalized with materials capable of charge transfer, H-bonding or electrostatic interactions with analytes for pre-concentration and electrocatalysis on their surface, whereas nanobio-electrosensors use analyte-selective aptamers having specific sequences of DNA, peptides or proteins to change the potential or current. This review intends to provide a combination of information related to MIPs and nanomaterial-based electrochemical sensors, limited to the most significant and illustrative work recently published. 相似文献
997.
Goral Levent Sezen Meltem Ow-Yang Cleva W. Günhan Büşra Buyukaksoy Aligul 《Journal of Solid State Electrochemistry》2023,27(3):655-666
Journal of Solid State Electrochemistry - A powder-free solid oxide cell electrode fabrication route is demonstrated, in which a polymeric precursor, containing the cations of electrocatalyst and... 相似文献
998.
László Csaba Bencze Csaba Paizs Monica Ioana Toşa Florin Dan Irimie 《Tetrahedron: Asymmetry》2010,21(3):356-364
In this Letter the baker’s yeast-mediated biotransformation of variously substituted α-hydroxy- and α-acetoxymethyl-5-phenylfuran-2-yl-ethanones is described. The stereochemical outcome of the reactions was strongly influenced by the nature of the substituents on the phenyl ring. 相似文献
999.
1000.