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排序方式: 共有378条查询结果,搜索用时 203 毫秒
71.
Temiloluwa T. Adejumo Marianna Danopoulou Leandros P. Zorba Dr. Andrej Pevec Dr. Matija Zlatar Dr. Dušanka Radanović Milica Savić Prof. Dr. Maja Gruden Prof. Dr. Katarina K. Anđelković Prof. Dr. Iztok Turel Dr. Božidar Čobeljić Prof. Dr. Georgios C. Vougioukalakis 《欧洲无机化学杂志》2023,26(33):e202300193
Two new Zn(II) complexes bearing tridentate hydrazone-based ligands with NNO or NNS donor atoms were synthesised and characterised by elemental analysis, infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies, and single crystal X-ray diffraction methods. These complexes, together with four previously synthesised analogues, having hydrazone ligands with a NNO donor set of atoms, were successfully employed as catalysts in the ketone-amine-alkyne (KA2) coupling reaction, furnishing tetrasubstituted propargylamines, compounds with unique applications in organic chemistry. DFT calculations at the CAM-B3LYP/TZP level of theory were performed to elucidate the electronic structure of the investigated Zn(II) complexes, excellently correlating the structure of the complexes to their catalytic reactivity. 相似文献
72.
73.
74.
Kramberger P Peterka M Boben J Ravnikar M Strancar A 《Journal of chromatography. A》2007,1144(1):143-149
Drawbacks of conventional virus purification methods have led to the development of new, mostly chromatography-based methods. Short monolithic columns are stationary phases intended for purification of large molecules. In this work efficient chromatographic purification of tomato mosaic virus (ToMV) from plant material is described. Based on short monolithic column, the purification process was shortened from 5 days to 2 hours. High viral purity was achieved and recovery of chromatographic step was up to 90%. In addition, these columns enabled preliminary quantification of the virus in just a few minutes, much faster than other quantification methods (e.g. enzyme-linked immunosorbent assay or real-time polymerase chain reaction) which take 1-2 days. These results demonstrate the potential of short monolith column technology for purification and analysis of different viruses. 相似文献
75.
Synthesis, characterization and cytotoxicity of surface amino-functionalized water-dispersible multi-walled carbon nanotubes 总被引:2,自引:0,他引:2
Goran Vukovi? Maja Obradovi? Miodrag ?oli? Petar S. Uskokovi? 《Applied Surface Science》2009,255(18):8067-8075
Surface functionalization of multi-walled carbon nanotubes (MWCNTs), with amino groups via chemical modification of carboxyl groups introduced on the nanotube surface, using O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (N-HATU) and N,N-diisopropylethylamine (DIEA) is reported. The N-HATU coupling agent provides faster reaction rate and the reaction occurs at lower temperature compared to amidation and acylation-amidation chemistry. The amines, 1,6-hexanediamine (HDA), diethylenetriamine (DETA), triethylenetetramine (TETA) and 1,4-phenylenediamine (PDA) were used. The resulting materials were characterized with different techniques such as FTIR, XRD, elemental analysis, TGA, TEM, UV-vis spectroscopy and cyclic voltammetry. MWCNTs functionalized with PDA posses the best dispersibility and electron transfer properties in comparison to the others amines. Functionalized MWCNTs, at the concentrations between 1 and 50 μg ml−1, were not cytotoxic for the fibroblast L929 cell line. However, the concentrations of MWCNTs higher of 10 μg ml−1 reduced cell growth and this effect correlated positively with the degree of their uptake by L929 cells. 相似文献
76.
Višnja Vrdoljak Ivica ĐilovićMarina Cindrić Dubravka Matković-ČalogovićNeven Strukan Astrid Gojmerac-IvšićPredrag Novak 《Polyhedron》2009
Eight new molybdenum(VI) complexes with 4-(diethylamino)salicylaldehyde and 2-hydroxy-3-methoxybenzaldehyde thiosemicarbazones have been prepared. They were characterized as mononuclear [MoO2LD] or dinuclear [{MoO2L}2D] complexes. In all the compounds the MoO22+ core is coordinated by a tridentate ONS thiosemicarbazonato ligand and by the N-donor molecule (imidazole, pyridine or γ-picoline). All the complexes were characterized by chemical analysis, IR spectroscopy and thermogravimetry. Three of the mononuclear complexes, dioxo[(2-hydroxy-3-methoxybenzaldehyde thiosemicarbazonato)(pyridine)]molybdenum(VI), dioxo[(2-hydroxy-3-methoxybenzaldehyde thiosemicarbazonato)(γ-picoline)]molybdenum(VI) and dioxo[(2-hydroxy-3-methoxybenzaldehyde thiosemicarbazonato)(imidazole)]molybdenum(VI) were also characterized by single-crystal X-ray structural analysis. A spectrophotometric method for the determination of molybdenum based on extraction of ion-pairs formed by the cationic surfactant and the [MoO(SCN)4]− anion is described. 相似文献
77.
Ion Gutiérrez-Aguirre Marko Banjac Andrej Steyer Mateja Poljšak-Prijatelj Matjaž Peterka Aleš Štrancar Maja Ravnikar 《Journal of chromatography. A》2009,1216(13):2700-2704
Rotaviruses are the leading cause of diarrhoea in infants around the globe and, under certain conditions they can be present in drinking water sources and systems. Ingestion of 10–100 viral particles is enough to cause disease, emphasizing the need for sensitive diagnostic methods. In this study we have optimized the concentration of rotavirus particles using methacrylate monolithic chromatographic supports. Different surface chemistries and mobile phases were tested. A strong anion exchanger and phosphate buffer (pH 7) resulted in the highest recoveries after elution of the bound virus with 1 M NaCl. Using this approach, rotavirus particles spiked in 1 l volumes of tap or river water were efficiently concentrated. The developed concentration method in combination with a real time quantitative polymerase chain reaction assay detected rotavirus concentrations as low as 100 rotavirus particles/ml. 相似文献
78.
We continue our use of “simple” energetic patterns, where simple means the use of parameters derived only from the stoichiometry
of these species in our studies of the entropy of formation (TΔf
S
o) of aqueous anions. Relationships between the entropy of formation and different parameters such as the number of oxygen
atoms, the natural logarithm of the molecular weight and the total number of atoms are explored. The charge of the species,
z− continues to be explicitly considered where we now explore various choices of p and use of z
p as a parameter. 相似文献
79.
Maja Ludvigsen Morten Østergaard Henrik Vorum Christian Jacobsen Bent Honoré 《BMC biochemistry》2009,10(1):34-11
Background
We have previously identified endonuclein as a cell cycle regulated WD-repeat protein that is up-regulated in adenocarcinoma of the pancreas. Now, we aim to investigate its biomedical functions. 相似文献80.