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91.
K. Andersson G. Borchardt S. Scherrer S. Weber 《Fresenius' Journal of Analytical Chemistry》1989,333(4-5):383-385
Summary The use of neutral primary particles for secondary ion mass spectrometry (NPB-SIMS) makes it possible to analyse the isotope concentration profiles of all constituent elements in Mg2SiO4 simultaneously. The results indicate
Selbstdiffusion in Mg2SiO4 (Forsterit) bei hoher Temperatur: Modelluntersuchung für SIMS-Analysen an keramischen Oberflächen相似文献
92.
Summary The composition of the eluent system in some instances determines the resolution and elution order of solutes in the reversed-phase chromatographic separation on cyclodextrin stationary phases. Both the identity and the concentration of the organic modifier can play a large role. The effect is particularly pronounced with naphthalene and its methyl derivatives with alcohol eluents.
Elutionsfolge bei der Flüssig-Chromatographie auf Cyclodextrinphasen. Abhängigkeit vom Gehalt an organischem Modifier im Eluenten相似文献
93.
D. Nilsson J. -O. Adler B. -E. Andersson K. I. Blomqvist L. Isaksson A. Sandell B. Schröder K. Ziakas L. Van Hoorebeke D. Ryckbosch R. Van de Vyver 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(2):239-240
The high spin structure of the nucleus129Ba has been investigated using a18O induced reaction. The known bands could be followed up to a maximum spin (55/2) ?. Some 56 states and 78 transitions could be placed in the level scheme. Band crossings were established in both positive and negative parity structures. They display features of strong polarization effects due to the alignment of h11/2 protons. 相似文献
94.
95.
Lele Duan Yunhua Xu Dr. Mikhail Gorlov Dr. Lianpeng Tong Samir Andersson Licheng Sun Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4659-4668
Two mononuclear ruthenium complexes [RuL(pic)3] ( 1 ) and [RuL(bpy)(pic)] ( 2 ) (H2L=2,6‐pyridinedicarboxylic acid, pic=4‐picoline, bpy=2,2′‐bipyridine) have been synthesized and fully characterized. Both complexes could promote water oxidation chemically and photochemically. Compared with other known ruthenium‐based water oxidation catalysts using [Ce(NH4)2(NO3)6] (CeIV) as the oxidant in solution at pH 1.0, complex 1 is one of the most active catalysts yet reported with an initial rate of 0.23 turnover s?1. Under acidic conditions, the equatorial 4‐picoline in complex 1 dissociates first. In addition, ligand exchange in 1 occurs when the RuIII state is reached. Based on the above observations and MS measurements of the intermediates during water oxidation by 1 using CeIV as oxidant, [RuL(pic)2(H2O)]+ is proposed as the real water oxidation catalyst. 相似文献
96.
Henrik Andersson Bertil Kågedal Carl-Fredrik Mandenius 《Analytical and bioanalytical chemistry》2010,398(3):1395-1402
Troponin T (TnT) is a useful biomarker for studying drug-induced toxicity effects on cardiac cells. We describe how a surface
plasmon resonance (SPR) biosensor was applied to monitor the release of TnT from active HL-1 cardiomyocytes in vitro when
exposed to cardiotoxic substances. Two monoclonal human TnT antibodies were compared in the SPR immunosensor to analyse the
TnT release. The detection limit of TnT was determined to be 30 ng/ml in a direct assay set-up and to be 10 ng/ml in a sandwich
assay format. Exposure of the cardiomyocytes to doxorubicin, troglitazone, quinidine and cobalt chloride for periods of 6
and 24 h gave significant SPR responses, whereas substances with low toxicity showed insignificant effects (ascorbic acid,
methotrexate). The SPR results were verified with a validated immunochemiluminescence method which showed a correlation of
r
2 = 0.790. 相似文献
97.
Andersson M Hedin J Johansson P Nordström J Nydén M 《The journal of physical chemistry. A》2010,114(50):13146-13153
Synthetic imidazole ligands are typically substituted at the N(1) ((1)-Im) position while natural imidazole ligands are substituted at the C(4) ((4)-Im) position. To outline the difference in coordination properties, the methyl-substituted imidazoles Me(4)-Im and Me(1)-Im were complexed with CuCl(2) and ZnCl(2) and investigated by NMR relaxometry, electron paramagnetic resonance, far-Fourier transform IR vibrational spectroscopy, and ab initio calculations. Me(4)-Im, Me(1)-Im, and Im in excess form the usual tetragonal D(4h) [CuL(4)X(2)] complexes with CuCl(2) whereas the methylated imidazoles form pseudotetrahedral C(2v) complexes instead of the usual octahedral O(h) [ZnIm(6)](2+) complex. All imidazoles display a high degree of covalence in the M-L σ- and π-bonds and the π-interaction strength affects the relative energies of complexation. Opportunities to tailor complexes by the chemical properties of the substituents are envisaged due to the role of the inductive and hyperconjugative effects, rather than position. 相似文献
98.
Javier Mazuela Alexander Paptchikhine Oscar Pàmies Pher G. Andersson Montserrat Diéguez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4567-4576
A library of readily available phosphite–oxazole/thiazole ligands ( L1 a – g – L7 a – g ) was applied in the Ir‐catalyzed asymmetric hydrogenation of several largely unfunctionalized E‐ and Z‐trisubstituted and 1,1‐disubstituted terminal alkenes. The ability of the catalysts to transfer chiral information to the product could be tuned by choosing suitable ligand components (bridge length, the substituents in the heterocyclic ring and the alkyl backbone chain, the configuration of the ligand backbone, and the substituents/configurations in the biaryl phosphite moiety), so that enantioselectivities could be maximized for each substrate as required. Enantioselectivities were therefore excellent (enantiomeric excess (ee) values up to >99 %) for a wide range of E‐ and Z‐trisubstituted and 1,1‐disubstituted terminal alkenes. The biaryl phosphite moiety was a very advantageous ligand component in terms of substrate versatility. 相似文献
99.
Johanna Andersson Dr. Minna Li Prof. Per Lincoln 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(36):11037-11046
The binuclear ruthenium complex [μ‐bidppz(phen)4Ru2]4+ has been extensively studied since the discovery of its unusual threading intercalation interaction with DNA, a binding mode with extremely slow binding and dissociation kinetics. The complex has been shown to be selective towards long stretches of alternating AT base pairs, which makes it interesting, for example, as a model compound for anti‐malaria drugs due to the high AT content of the genome of the malaria parasite P. falciparum. We have investigated the effect of bridging ligand structure on threading intercalation ability and found that length and rigidity as well as the size of the intercalated ring system are all factors that affect the rate and selectivity of the threading intercalation. In particular, we discovered a new DNA‐threading compound, [μ‐dppzip(phen)4Ru2]4+, which appears to be just at the border of being capable of threading intercalation and displays even greater selectivity for AT‐DNA than the parent compound, [μ‐bidppz(phen)4Ru2]4+. 相似文献
100.
Paul T. Allen Lars Andersson Alvaro Restuccia 《Communications in Mathematical Physics》2011,301(2):383-410
In this paper we consider the classical initial value problem for the bosonic membrane in light cone gauge. A Hamiltonian
reduction gives a system with one constraint, the area preserving constraint. The Hamiltonian evolution equations corresponding
to this system, however, fail to be hyperbolic. Making use of the area preserving constraint, an equivalent system of evolution
equations is found, which is hyperbolic and has a well-posed initial value problem. We are thus able to solve the initial
value problem for the Hamiltonian evolution equations by means of this equivalent system. We furthermore obtain a blowup criterion
for the membrane evolution equations, and show, making use of the constraint, that one may achieve improved regularity estimates. 相似文献