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41.
Rudolf Taube Karl Seyferth Lajos Bencze Laszlo Markó 《Journal of organometallic chemistry》1976,111(2):215-223
The reaction of di- and mono-nitrosylmolybdenum complexes with C2H5-AlCl2, AlCl3 and Al(C2H5)3 under argon and CO was followed IR-spectroscopically. Some conclusions were reached concerning the nature of the catalyticactivity of the complex in olefin metathesis. 相似文献
42.
Intranasal irradiation with the xenon chloride ultraviolet B laser improves allergic rhinitis 总被引:1,自引:0,他引:1
Csoma Z Ignacz F Bor Z Szabo G Bodai L Dobozy A Kemeny L 《Journal of photochemistry and photobiology. B, Biology》2004,75(3):137-144
We earlier reported that the 308 nm xenon chloride (XeCl) ultraviolet B (UVB) laser is highly effective for the treatment of inflammatory skin diseases. Since UVB irradiation has been shown to exert both local and systemic immunosuppression, we investigated the clinical efficacy of UVB irradiation in allergic rhinitis. In an open study, groups of patients with severe allergic rhinitis received intranasal irradiation with a 308 nm XeCl UVB excimer laser for two weeks. In the low-dose group (n=10), treatment was given twice weekly, starting with 0.25x the individual minimal erythema dose (MED), whereas patients in the medium-dose group (n=8) were treated four times weekly, starting with 0.4x MED. In each group, the dosage was gradually increased. Evaluation was based on the symptom scores. The effect of the XeCl laser on the skin prick test reaction was also studied. In the low-dose group, seven patients completed the study, and there was no improvement in the nasal symptoms. In the medium-dose group, the XeCl UVB irradiation significantly inhibited the rhinorrhoea, the sneezing, the nasal obstruction and the total nasal score (p<0.05). The XeCl UVB excimer laser also inhibited the allergen-induced skin prick test in a dose-dependent manner. These results suggest that the XeCl UVB excimer laser might serve as a new therapeutic tool in the treatment of allergic rhinitis. 相似文献
43.
44.
Synthesis,solid-state photophysical properties and electropolymerization of novel diazulenyl ethenes
Eugenia Andreea Dragu Simona Nica Matei Raicopol Adriana Baran Dan-Florin Anghel Bogdan Cojocaru Laszlo Tarko Alexandru C. Razus 《Tetrahedron letters》2012,53(21):2611-2614
The novel 1,2-di(azulen-1-yl)cyclopent-1-ene 3 was conveniently synthesized via a two-step procedure involving Vilsmeier–Haack acylation of azulene with N,N,N′,N′-tetraethylglutaramide (TEGA) and POCl3, followed by an intramolecular McMurry coupling of the resulting diketone. In contrast with the previously reported (E)-1,2-di(azulen-1-yl)ethene that shows negligible fluorescence in the solid state, alkene 3 displays fluorescence emission from the S2 excited state of the azulene moieties. This compound easily polymerizes upon electrochemical oxidation, leading to the formation of a conducting polymer film at the electrode surface. 相似文献
45.
Claude St. Thomas Hortensia Maldonado‐Textle Antal Rockenbauer Laszlo Korecz Nora Nagy Ramiro Guerrero‐Santos 《Journal of polymer science. Part A, Polymer chemistry》2012,50(14):2944-2956
Two different initiator/transfer agents (inifers) containing an alkoxyamine and a dithiobenzoate were synthetized and used to trigger out either reversible addition‐fragmentation chain transfer (RAFT) polymerization or nitroxide‐mediated polymerization (NMP). α‐Dithiobenzoate‐ω‐alkoxyamine‐difunctional polymers were produced in both cases which were subsequently used as precursors in the formation of block copolymers. This synthetic approach was applied to N‐isopropylacrylamide (NIPAM) or polyethylene oxide methacrylate (EOMA) to form α,ω‐heterodifunctional homopolymers via RAFT at 60°C which were chain extended with styrene by activating the alkoxyamine moiety at 120°C. Under such temperature conditions, it is proposed that a tandem NMP/RAFT polymerization is initiated producing a simultaneous growth of polystyrene blocks at both chain‐ends. Self‐assembled nanostructures of these amphiphilic block copolymers were evidenced by scanning electron microscopy. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
46.
Reza Porouchani Laszlo Garamszegi Tuan Q. Nguyen Jns Hilborn 《Macromolecular rapid communications》2000,21(12):837-840
Narrow polydispersity polystyrene with a molecular weight of 1.03×106 has been functionalized with anthracene groups using the metallocene technique. Side reactions such as chain coupling and bond scission can be limited by working in THF at –75°C. Gel permeation chromatography combined with on‐line viscometric, refractive index and fluorescence detection allows us to verify that degradation did not exceed 1 bond scission/180 000 monomer units. The degree of grafting increases with the reaction time but remains modest (< 5% after 7 h) at low temperature. 相似文献
47.
Shao Y Molnar LF Jung Y Kussmann J Ochsenfeld C Brown ST Gilbert AT Slipchenko LV Levchenko SV O'Neill DP DiStasio RA Lochan RC Wang T Beran GJ Besley NA Herbert JM Lin CY Van Voorhis T Chien SH Sodt A Steele RP Rassolov VA Maslen PE Korambath PP Adamson RD Austin B Baker J Byrd EF Dachsel H Doerksen RJ Dreuw A Dunietz BD Dutoi AD Furlani TR Gwaltney SR Heyden A Hirata S Hsu CP Kedziora G Khalliulin RZ Klunzinger P Lee AM Lee MS Liang W Lotan I Nair N Peters B Proynov EI Pieniazek PA Rhee YM 《Physical chemistry chemical physics : PCCP》2006,8(27):3172-3191
Advances in theory and algorithms for electronic structure calculations must be incorporated into program packages to enable them to become routinely used by the broader chemical community. This work reviews advances made over the past five years or so that constitute the major improvements contained in a new release of the Q-Chem quantum chemistry package, together with illustrative timings and applications. Specific developments discussed include fast methods for density functional theory calculations, linear scaling evaluation of energies, NMR chemical shifts and electric properties, fast auxiliary basis function methods for correlated energies and gradients, equation-of-motion coupled cluster methods for ground and excited states, geminal wavefunctions, embedding methods and techniques for exploring potential energy surfaces. 相似文献
48.
Eva Vergucht Björn De Samber Andrei Izmer Bart Vekemans Karen Appel Sergei Tolmachev Laszlo Vincze Frank Vanhaecke 《Analytical and bioanalytical chemistry》2015,407(6):1559-1566
This study aims at evaluating the capabilities of synchrotron radiation micro X-ray fluorescence spectrometry (SR micro-XRF) for qualitative and semi-quantitative elemental mapping of the distribution of actinides in human tissues originating from individuals with documented occupational exposure. The investigated lymph node tissues were provided by the United States Transuranium and Uranium Registries (USTUR) and were analyzed following appropriate sample pre-treatment. Semi-quantitative results were obtained via calibration by external standards and demonstrated that the uranium concentration level in the detected actinide hot spots reaches more than 100 μg/g. For the plutonium hot spots, concentration levels up to 31 μg/g were found. As illustrated by this case study on these unique samples, SR micro-XRF has a high potential for this type of elemental bio-imaging owing to its high sensitivity, high spatial resolution, and non-destructive character.
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相似文献
49.
Matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) have been used in conjunction with time-of-flight (TOF) and quadrupole ion trap (IT) mass spectrometry, respectively, to analyze various cytolysin proteins isolated from the sea anemone Stichodactyla helianthus and digested by the protease trypsin. By employing different ionization methods, the subsequent changes in ionization selectivity for the peptides in the digested protein samples resulted in ion abundance variation reflected in the mass spectra. Upon investigation of this variation generated by the two ionization processes, it has been shown in this study that enhanced protein coverage (e.g., >95% for cytolysin III) can be achieved. Additionally, capillary and microbore reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with ESI mass spectrometry (MS) as well as flow injection analysis by nanoflow ESI-MS afforded the necessary limit of detection (LOD) for detailed structural information of the cytolysin proteins by tandem mass spectrometry (MS/MS) methods. It can be concluded that cytolysins II and III correspond to sticholysins I and II, that "cytolysin I" is a mixture of modified forms of cytolysins II and III, and that "cytolysin IV" is an incompletely processed precursor of cytolysin III. 相似文献
50.
Tolvaj L Persze L Albert L 《Journal of photochemistry and photobiology. B, Biology》2011,105(1):90-93
In this study, wood samples were exposed to light irradiations (direct sunlight, xenon lamp, mercury vapour lamp) and thermal treatments were carried out in dry- and in humid conditions at 90°C. One part of the samples was covered by an aluminium plate during light irradiation. The samples under the aluminium plate also suffered considerable chemical changes, monitored by infrared technique and colour measurement. The sunlight produced greater colour change under the aluminium plate than the artificial light sources. During light irradiation, the carbonyl band having two maximum at 1700 and 1,746 cm(-1) increased and the peak of the aromatic skeletal vibration arising from lignin (1,510 cm(-1)) decreased together with the guaiacyl vibrations at 1,275 cm(-1). There was absorption decrease at 1,174 cm(-1) because of the ether band splitting. Under the covered surface only the ether band at 1,174 cm(-1) decreased and one carbonyl band increased with a maximum at 1,715 cm(-1). Degradation of lignin was negligible for the covered surface. Colour change generated by thermal degradation was much greater in humid condition than in dry condition. 相似文献