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61.
The synthesis of [1]benzothieno[2,3-c][1,10]phenanthroline ( 5 ) is described. It was obtained in four steps from known starting materials. The basic skeleton of the molecule and of the phenanthroline ring were formed via photocyclization. The total assignment of 1H-nmr spectra was accomplished with the aid of two-dimensional nmr methods. 相似文献
62.
Congreve A Parker D Gianolio E Botta M 《Dalton transactions (Cambridge, England : 2003)》2004,(9):1441-1445
Detailed analyses of the solution structure and exchange dynamics of two sets of homologous mono-amide triacetate lanthanide complexes (Ln = Eu, Gd) of cyclen have been undertaken. The complex [LnL1], bearing an N-linked CH2CH2NHCO-pyridyl moiety, forms mono-aqua (q = 1) species in solution and the Gd complex undergoes rapid water exchange (k(ex)= 11 x 10(7) s(-1), 298 K) as a result of the steric destabilisation of the Ln-water binding interaction. The homologous complex with a C-3 spacing chain, [LnL2], forms a q = 0 species. 相似文献
63.
Rui Min Vivian Goh Kim Huey Ee Aileen Pua Yunle Huang Shao Quan Liu Benjamin Lassabliere Bin Yu 《Journal of mass spectrometry : JMS》2022,57(2):e4810
In this study, neutral loss scan and high-resolution MS/MS were used in combination to detect and tentatively identify various flavonoid and limonoid glycosides in navel orange albedo, juice, peel and pulp. These compound classes are of research interest due to their flavour and bioactive properties, and although flavonoid glycosides have been previously studied in other food matrices, to the best of our knowledge, neutral loss scans have not been used for the elucidation of limonoid glycosides. Neutral loss masses of 120, 162 and 308 Da were selected for the detection of hexose, rutinose and neohesperidose-substituted flavonoids, whereas 197 Da was explored for limonoid glycosides due to their tendency to form ammonium adducts. Fragmentation patterns obtained from targeted MS/MS were then used to differentiate rutinose and neohesperidose substituents as well as flavonoid subclasses of flavones, flavanones and flavonols. Additionally, high-resolution MS/MS was also used for the identification of aglycones by accurate mass (to four decimal places), allowing for the differentiation of aglycones with similar unit masses but different chemical formulas. In total, 19 flavonoid glycosides and six limonoid glycosides were detected. This workflow allows for a rapid screening of flavonoid and limonoid glycosides in citrus, which can be further extended to other food products such as tea. 相似文献
64.
65.
Takamura Yasuhiro Leonard Kwati Luo Aileen Martin Lane W. Matsumoto Hiroshige 《Journal of Solid State Electrochemistry》2019,23(3):953-963
Journal of Solid State Electrochemistry - Heterointerfaces introduce unique localized defects into ionic conductors. This study explores the nanoionic characteristics exhibited by the... 相似文献
66.
Summary: This work demonstrated the severity of heterogeneity issues with ampoule reactors in bulk atom transfer radical polymerization of methyl methacrylate. The kinetic data of CuII concentration, monomer conversion, and polymer molecular weight varied from location to location along the ampoule. However, the polymer molecular weight versus conversion data from different locations fell into a single theoretical line. All locations except for the bottom part of the ampoule produced polymers having narrow molecular weight distribution.
67.
Valentina Hilberg Dr. Olga Avrutina Aileen Ebenig Desislava Yanakieva Dr. Tobias Meckel Prof. Dr. Markus Biesalski Prof. Dr. Harald Kolmar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1746-1751
Efficient and reliable methods for the generation of bioactive papers are of growing interest in relation to point-of-care testing devices that do not require extensive analytical equipment. Herein, we report the immobilization of functional proteins on paper fibers using a modular chemoenzymatic approach. The synthetic strategy relies on a combination of highly efficient spatially controllable photo-triggered cycloaddition followed by site-specific sortase A-catalyzed transamidation. This site-directed and regiospecific method has allowed unidirectional and covalent immobilization of several proteins displaying different functional properties, with ramifications for application in paper-based diagnostics. 相似文献
68.
Jamshed Iqbal Aileen F. Knowles Christa E. Müller 《Journal of chromatography. A》2010,1217(4):600-604
A simple and fast method of immobilization of cell membrane suspension containing human ecto-nucleoside triphosphate diphosphohydrolase 2 (NTPDase2) on a polyacrylamide-coated capillary was developed. The enzyme microbioreactor was prepared by hydrodynamic injection of a small plug of the polycationic electrolyte hexadimethrine bromide (HDB) followed by a suspension of an enzyme-containing membrane preparation. In order to shorten the enzyme assay time and to increase the throughput of the assay, the capillary was coated from the outlet end and all injections were performed from the outlet end of the capillary. For the monitoring of the enzymatic reaction, the substrate ATP dissolved in reaction buffer (140 mM NaCl, 5 mM KCl, 1 mM MgCl2, 2 mM CaCl2, and 10 mM Hepes, pH 7.4, internal standard: 10 μM UMP) in the absence or presence of inhibitor was injected electrokinetically and incubated in the microbioreactor for 1 min with 1 kV of applied voltage. Then, the electrophoretic separation of the reaction products was initiated by applying a constant current of 60 μA. A 50 mM phosphate buffer (pH 6.5) was used for the separations and the products were detected by UV absorbance at 260 nm. The new method was compared with an at-capillary-inlet method without immobilization of the enzyme. The results (Km values, Ki values for inhibitor) obtained with both methods were similar and comparable with literature data. The developed outlet immobilized enzyme microreactor using a coated capillary is very fast, simple and most economic allowing multiple use of the enzyme. 相似文献
69.
James P. Scarth Adam Clarke Jonathan Hands Philip Teale Aileen C. Mill Roy Macarthur Jack Kay Hubert De Brabander 《Chromatographia》2010,72(3-4):297-305
The use of anabolic steroids as growth promoting agents in food production is prohibited under European Union legislation, but there is currently no internationally accepted method for detecting the abuse of the anabolic steroid nandrolone in the porcine. Therefore, an analytical biomarker approach based on gas chromatography-tandem mass spectrometry (GC-MS-MS) analysis of the major urinary free fraction nandrolone metabolite 19-noretiocholanolone was developed and validated. The lower and upper limits of quantification of the assay were 25 and 3,000 pg mL?1 respectively. The limit of detection was calculated as 13.2 pg mL?1, which is significantly lower than previously reported methods. When applied to a population of untreated animals, 19-noretiocholanolone distributions in boars and gilt were bimodal, with a small number of concentrations in each sex at around the 1,000 pg mL?1 region and the majority of concentrations closer to the lower end of the calibration range. Statistical analysis of the data was carried out in order to suggest screening and confirmatory threshold approaches for this steroid in the urine of boars and gilts. The adopting of particular screening thresholds would be at the discretion of the individual regulating authorities, but at a false non-compliance rate of 1 in 10,000 of the normal population, the suggested confirmatory thresholds (7,501.6 pg mL?1 for boars and 19,200.4 pg mL?1 in gilts) are able to detect the abuse of nandrolone for several weeks following administration of this steroid. 相似文献
70.
Maja Miletić Dragana Vuković Irena Živanović Ivana Dakić Ivan Soldatović Dejan Maletić Saša Lazović Gordana Malović Zoran Lj. Petrović Nevena Puač 《Central European Journal of Physics》2014,12(3):160-167
In numerous recent papers plasma chemistry of non equilibrium plasma sources operating at atmospheric pressure has been linked to plasma medical effects including sterilization. In this paper we present a study of the effectiveness of an atmospheric pressure plasma source, known as plasma needle, in inhibition of the growth of biofilm produced by methicillin resistant Staphylococcus aureus (MRSA). Even at the lowest powers the biofilms formed by inoculi of MRSA of 104 and 105 CFU have been strongly affected by plasma and growth in biofilms was inhibited. The eradication of the already formed biofilm was not achieved and it is required to go to more effective sources. 相似文献