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排序方式: 共有363条查询结果,搜索用时 46 毫秒
81.
82.
Lenka V. Tamayo Ana E. Burgos Pedro F. B. Brandão 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):52-59
Abstract The synthesis and characterization of a new palladium(II) complex [Pd(MePhPzTSC)2] and its corresponding ligand 3-methylpyrazole-4-carboxaldehyde thiosemicarbazone (MePhPzTSC) are described. The bidentate ligand is coordinated to Pd(II) through the azomethine nitrogen atoms and sulfur in the form of thiol by deprotonation of the NH-C = S. The antimicrobial activity of these new compounds was evaluated against gram-negative (Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus and Bacillus thuringiensis) bacteria and two yeast strains (Candida albicans and Saccharomyces cerevisiae). Coordination of the ligand to the metallic ion showed improved antimicrobial activity compared to the free ligand. For the gram-positive bacteria the antimicrobial activity of the complex was higher than that of the positive control used. [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 following free supplemental files: Additional figures and tables] 相似文献
83.
Lenka Chvátalová Roman Čermák Aleš Mráček Ondřej Grulich Alenka Vesel Petr Ponížil Antonín Minařík Uroš Cvelbar Lubomír Beníček Petr Sajdl 《European Polymer Journal》2012,48(4):866-874
This paper is focused on the chemical and morphology changes in the surface of poly(1-butene) (PB-1) generated by plasma treatment. The radio frequency capacitively coupled plasma (air, argon, argon then allylamine, argon containing ammonia and argon with octafluorocyclobutane) was used. Modified surface of PB-1 was characterized by contact angle measurements, X-ray photoelectron spectroscopy, and atomic force microscopy. The surface hydrophilization by air and argon with ammonia plasmas was evaluated as most sufficient. Oppositely, a high level of hydrophobicity of PB-1 surface was reached by combination of argon with octafluorocyclobutane plasma. Upon plasma modification, hydrophilicity/hydrophobicity of treated surfaces remained stable within three days under air atmosphere and then values of contact angle slowly recovered to those of unmodified PB-1. However, morphology and surface chemical composition of plasma-modified samples remained generally unchanged during observed time. Changes in surface hydrophilicity/hydrophobicity of plasma-treated PB-1 were attributed to variance of conformation of the surface molecules. 相似文献
84.
Jiří Plíšek Lenka Kujovská Krčmová Jana Aufartová Tanausú V. Morales Sarah M. Esponda Roman Oros Eva Kasalová Jose J. Santana‐Rodriguez Luboš Sobotka Petr Solich Dagmar Solichová 《Journal of separation science》2013,36(23):3702-3708
Biomarkers, 25‐hydroxyvitamin D3 and 25‐hydroxyvitamin D2, are important indicators of the vitamin D general status and are monitored in several pathophysiological disorders, such as osteoporosis, diabetes, heart disease, etc. A novel ultra‐HPLC with MS/MS methodology for the analysis of 25‐hydroxyvitamin D derivatives coupled with a very simple and highly rapid sample preparation step was developed. Analytical parameters obtained showed linearity (R2) above 0.999 for both vitamins with accuracies between 95.8 and 102%. The LODs were as low as 0.22 and 0.67 nmol/L for 25‐hydroxyvitamin D3 and 25‐hydroxyvitamin D2, respectively. Intra‐assay precision (%RSD) was lower than 4.5%, and inter‐assay precision (%RSD) was lower than 6.5%. The feasibility of the developed methodology to be applied in clinical routine analysis has been proved by its application in blood samples from non‐agenarian patients, patients with familial hypercholesterolemia and patients suffering from age‐related macular degeneration. 相似文献
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86.
Bueno Justin Halámková Lenka Rzhevskii Alexander Lednev Igor K. 《Analytical and bioanalytical chemistry》2018,410(28):7295-7303
Analytical and Bioanalytical Chemistry - Our research group previously reported a novel method for the detection of gunshot residue (GSR) via tape lifting combined with Raman microspectroscopic... 相似文献
87.
Laboratory experiments involving shutdown and repeated start-up of a denitrification USB reactor with granulated anoxic biomass were conducted in order to find suitable conditions for a safe storage period of the biomass. Anoxic granulated biomass stored under anaerobic conditions for a half year period at 6°C and for a half month period at 18–20°C retained its activity and granular morphology. Storage of anoxic granules under anaerobic conditions for a half year period at 18–20°C led to the loss of the biomass original activity and a significant portion of the granules disintegrated. Anoxic granulated biomass stored for a one and a half month period under endogenous anoxic conditions at 18–20°C retained its activity and granular morphology. A two month storage under endogenous anoxic conditions at 18–20°C was too long and the shutdown of the reactor had to be followed by repeated anoxic granulation. Minimum loading of the USB reactor with N-NO3 to maintain endogenous anoxic conditions in the sludge bed was in the range of 0.06–0.1 kg of N-NO3 per m3 per day. Restart of the USB reactor can be accelerated by an addition of anaerobic granulated biomass. 相似文献
88.
Abstract 4-Acetyl-phenyl acrylate was prepared by reacting 4-hydroxy acetophenone with acryloyl chloride. It was then polymerized using benzoyl peroxide (BPO) as initiator to give the homopolymer. Both the vinylmonomer and its homopolymer were characterized by FTIR spectra. The polyurethane obtained from castor oil and TDI (Toluene-2,4-diisocyanate) with varying NCO/OH ratio was reacted with the new monomer 4-acetyl phenyl acrylate to give a large number of interpenetrating polymer networks (IPNs) using divinyl benzene as cross-linker and BPO as initiator. The thermogravimetric studies of the IPNs have been carried out and the kinetic parameters have been evaluated. 相似文献
89.
Ohne Zusammenfassung 相似文献
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