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951.
Bettina Wehring Lukas Gerlich Alireza M. Kia Marcus Wislicenus Benjamin Uhlig 《Surface and interface analysis : SIA》2020,52(12):962-967
We demonstrate the utilization of parallel angle-resolved X-ray photoelectron spectroscopy (pAR-XPS) as a useful tool to analyze ultrathin sputtered tantalum nitride (TaN) thin films in complementary metal-oxide-semiconductor (CMOS) trenches. The chemical composition of TaN was estimated by pAR-XPS using a Theta 300i from Thermo Fischer. An improved lateral resolution was achieved by analyzing periodic structures. The XPS data was correlated with transmission electron microscopy (TEM) in combination with energy-dispersive X-ray spectroscopy (EDX) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) data. The results show that the nitrogen content in the TaN thin films was about 6% higher at the sidewall compared with the top and bottom of the trench. 相似文献
952.
953.
Dennis Kubiczek Carolin Flaig Heinz Raber Steffen Dietz Ann‐Kathrin Kissmann Thomas Heerde Nicholas Bodenberger Andreas Wittgens Melaine Gonzlez‐Garcia Fan Kang Octavio L. Franco Ludger Staendker Anselmo J. Otero‐Gonzlez Paul Walther Kay E. Gottschalk Tanja Weil Frank Rosenau 《Macromolecular bioscience》2020,20(4)
The pathogenic yeast Candida auris has received increasing attention due to its ability to cause fatal infections, its resistance toward important fungicides, and its ability to persist on surfaces including medical devices in hospitals. To brace health care systems for this considerable risk, alternative therapeutic approaches such as antifungal peptides are urgently needed. In clinical wound care, a significant focus has been directed toward novel surgical (wound) dressings as first defense lines against C. auris. Inspired by Cerberus the Greek mythological “hound of Hades” that prevents the living from entering and the dead from leaving hell, the preparation of a gatekeeper hybrid hydrogel is reported featuring lectin‐mediated high‐affinity immobilization of C. auris cells from a collagen gel as a model substratum in combination with a release of an antifungal peptide drug to kill the trapped cells. The vision is an efficient and safe two‐layer medical composite hydrogel for the treatment of severe wound infections that typically occur in hospitals. Providing this new armament to the repertoire of possibilities for wound care in critical (intensive care) units may open new routes to shield and defend patients from infections and clinical facilities from spreading and invasion of C. auris and probably other fungal pathogens. 相似文献
954.
A new selective method for the determination of the bioactive amine gizzerosine in poultry feed is presented based on hydrophilic interaction chromatography coupled to electrospray ionisation and tandem quadrupole mass spectrometry. The protonated molecular ions were selected for fragmentation and scanning of the two major product ions using the mass analyser in the multiple reaction monitoring mode. The analytical methodology included acid hydrolysis of feed sample aliquots and desalting and crude clean-up of hydrolysates using cation-exchange chromatography on a polymeric solid-phase extraction sorbent. Mean overall recoveries (n = 9) were 68?C82% in spike-recovery experiments. The limit of detection was 0.25 mg kg?1. The method was applied to the analysis of fish meal and fish meal-containing poultry feed samples. Although gizzerosine could not be detected in any of the samples, it was found in fish meal made from sand eel after heating to 130 °C for 24 h. 相似文献
955.
Steffen Fischer Katrin Thümmler Bert Volkert Kay Hettrich Ingeborg Schmidt Klaus Fischer 《Macromolecular Symposia》2008,262(1):89-96
Cellulose acetate is one of the most important esters of cellulose. Depending on the way it has been processed cellulose acetate can be used for great varies of applications (e.g. for films, membranes or fibers). The properties of the applied cellulose acetates are very important for these applications. A special field for using cellulose acetate is the synthesis of porous, spherical particles, so called cellulose beads. Different types of technical cellulose acetates were used and their ability to form such cellulose beads was characterized. First the different types of cellulose acetates were characterized by means of solubility; turbidity and degree of substitution. In addition the molar mass and the distribution of substituents along the polymeric chain were analyzed. Next, the cellulose beads were synthesized within an emulsion process using these different cellulose acetates. Then the properties (particle size, porosity, morphology) of the cellulose beads were determined. Finally, the relationship between the characteristic of cellulose acetates and properties of cellulose beads was investigated. 相似文献
956.
We monitor and characterize near-surface diffusion of miscible, transparent liquids in a microfluidic device by third harmonic microscopy. The technique enables observations even of transparent or index-matched media without perturbation of the sample. In particular, we image concentrations of ethanol diffusing in water and estimate the diffusion coefficient from the third harmonic images. We obtain a diffusion coefficient D?=?(460?±?30) ??m2/s, which is consistent with theoretical predictions. The investigations clearly demonstrate the potential of harmonic microscopy also under the challenging conditions of transparent fluids. 相似文献
957.
Marie-Luise Lechner Katharina Fürpaß Roland C. Fischer Frank Uhlig 《Journal of organometallic chemistry》2009,694(26):4209-4215
The reaction of ditbutyldichlorostannane with 5 equivalents of magnesium leads to 1,1,2,2,3,3,4-hepta-tbutyl-4-(chloromagnesio)-tetrastannacyclobutane 1. A mechanism of this reaction is proposed. 1 is structurally characterized by 1D and 2D 119Sn NMR experiments. New monofunctionalised four membered cyclostannanes could be obtained by derivatisation of 1. X-Ray analysis of 1,1,2,2,3,3,4-hepta-tbutyl-4-methyl-tetrastannacyclobutane 2 and 1,1,2,2,3,3,4-hepta-tbutyl-4-chlorpropyl-tetrastannacyclobutane 5 show bent ring systems with folding angles about 157°. 相似文献
958.
Steffen Koenig 《Journal of Pure and Applied Algebra》2009,213(5):886-891
Suppose B is an algebra with a stratifying ideal BeB generated by an idempotent e. We will establish long exact sequences relating the Hochschild cohomology groups of the three algebras B, B/BeB and eBe. This provides a common generalization of various known results, all of which extend Happel’s long exact sequence for one-point extensions. Applying one of these sequences to Hochschild cohomology algebras modulo the ideal generated by homogeneous nilpotent elements shows, in some cases, that these algebras are finitely generated. 相似文献
959.
Steffen Oppermann 《Journal of Pure and Applied Algebra》2009,213(10):1945-2521
We show that any wild algebra has a one-point extension of representation dimension at least four, and more generally that it has an n-point extension of representation dimension at least n+3. We give two explicit constructions, and obtain new examples of small algebras of representation dimension four. 相似文献
960.
We describe the shape of the symplectic Dirac operators on Hermitian symmetric spaces. For this, we consider these operators
as families of operators that can be handled more easily than the original ones. 相似文献