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101.
C. el Dsoki A. Tomasella H. Hanselka H. Kaufmann 《Materialwissenschaft und Werkstofftechnik》2012,43(6):544-552
Suitable methods and transferability criteria and knowledge of the cyclic material behaviour is essential for a durable design of a component. For this reason, the cyclic material parameters are determined as a function of the product's properties (level of deformation, microstructure, surface finish, residual stresses) and different loading parameters. However, since the determination of the cyclic parameters is associated with considerable experimental effort and costs, a cost‐effective and easy method is sought to determine these parameters. A very promising approach for this is the application of artificial neural networks (ANN) since they have the ability to generate the influences on the fatigue strength from the manufacturing and environmental parameters using sensibly selected input parameters. They offer the possibility to access acquired knowledge and to thus construct a multidimensional map based on a few tests. By combining a few experimental tests with the ANN, the result of the estimation can be improved and the experimental effort can be reduced. 相似文献
102.
Jens Georg Kaufmann Marc P. Y. Desmulliez Yingtao Tian Dennis Price Mike Hughes Nadia Strusevich Chris Bailey Changqing Liu David Hutt 《Microsystem Technologies》2009,15(8):1245-1254
In this paper we propose an agitation method based on megasonic acoustic streaming to overcome the limitations in plating
rate and uniformity of the metal deposits during the electroplating process. Megasonic agitation at a frequency of 1 MHz allows
the reduction of the thickness of the Nernst diffusion layer to less than 600 nm. Two applications that demonstrate the benefits
of megasonic acoustic streaming are presented: the formation of uniform ultra-fine pitch flip-chip bumps and the metallisation
of high aspect ratio microvias. For the latter application, a multi-physics based numerical simulation is implemented to describe
the hydrodynamics introduced by the acoustic waves as they travel inside the deep microvias. 相似文献
103.
Elodie Belnoue Alexis Vogelzang Natalie E. Nieuwenhuizen Magdalena A. Krzyzaniak Stephanie Darbre Mario Kreutzfeldt Ingrid Wagner Doron Merkler Paul-Henri Lambert Stefan H. E. Kaufmann Claire-Anne Siegrist Daniel D. Pinschewer 《International journal of molecular sciences》2022,23(5)
Mycobacterium tuberculosis (Mtb) represents a major burden to global health, and refined vaccines are needed. Replication-deficient lymphocytic choriomeningitis virus (rLCMV)-based vaccine vectors against cytomegalovirus have proven safe for human use and elicited robust T cell responses in a large proportion of vaccine recipients. Here, we developed an rLCMV vaccine expressing the Mtb antigens TB10.4 and Ag85B. In mice, rLCMV elicited high frequencies of polyfunctional Mtb-specific CD8 and CD4 T cell responses. CD8 but not CD4 T cells were efficiently boosted upon vector re-vaccination. High-frequency responses were also observed in neonatally vaccinated mice, and co-administration of rLCMV with Expanded Program of Immunization (EPI) vaccines did not result in substantial reciprocal interference. Importantly, rLCMV immunization significantly reduced the lung Mtb burden upon aerosol challenge, resulting in improved lung ventilation. Protection was associated with increased CD8 T cell recruitment but reduced CD4 T cell infiltration upon Mtb challenge. When combining rLCMV with BCG vaccination in a heterologous prime-boost regimen, responses to the rLCMV-encoded Mtb antigens were further augmented, but protection was not significantly different from rLCMV or BCG vaccination alone. This work suggests that rLCMV may show utility for neonatal and/or adult vaccination efforts against pulmonary tuberculosis. 相似文献
104.
Kaufmann M Zweifel C Blanco M Blanco JE Blanco J Beutin L Stephan R 《Journal of food protection》2006,69(2):260-266
Fecal samples from 630 slaughtered finisher pigs were examined by PCR to assess the shedding of Escherichia coli O157 (rfbE) and Shiga toxin-producing E. coli (STEC, stx). The proportion of positive samples was 7.5% for rfbE and 22% for stx. By colony hybridization, 31 E. coli O157 and 45 STEC strains were isolated, and these strains were further characterized by phenotypic and genotypic traits. Among E. coli O157 strains, 30 were sorbitol positive, 30 had an H type other than H7, and none harbored stx genes. Intimin (eae), enterohemolysin (ehxA), EAST1 (astA), and porcine A/E-associated protein (paa) were present in 10, 3, 26, and 6% of strains. Among them, one eae-gamma1-positive O157:H7 strain testing positive for ehxA and astA and two eae-alpha1-positive O157:H45 strains were classified as enteropathogenic E. coli (EPEC). The O157:H45 EPEC harbored the EAF plasmid and the bfpA gene, factors characteristic for typical EPEC. The isolated STEC strains (43 sorbitol positive) belonged to 11 O:H serotypes, including three previously reported in human STEC causing hemolytic uremic syndrome (O9:H-, O26:H-, and O103:H2). All but one strain harbored stx2e. The eae and ehxA genes, which are strongly correlated with human disease, were present in only one O103:H2 strain positive for stx1 and paa, whereas the astA gene was found more frequently (14 strains). High prevalence of STEC was found among finisher pigs, but according to the virulence factors the majority of these strains seem to be of low virulence. 相似文献
105.
A Method for the Quantitative Control of Solid Phase Reactions in the Peptide Synthesis A quantitative control-method of partial steps of a solid phase peptide synthesis is described, based on a hydrazinolytic cleavage of protected peptides from the solid support. A separation of the peptide hydrazides by gelchromatography on sephadex G 15 in dimethylformamide and a quantitative evaluation of the hydrazide-content in the elution fractions is reported, which permits the control of the Nα-deprotection step in the same way as the evaluation of the coupling yields of the desired sequence. The new method is discussed for the example of two solid phase syntheses of the pentapeptide N-tert.-butyl-oxycarbonyl-L -valyl-S-benzyl-L -cysteinyl-L -alanyl-L - leucyl-O-benzyl-L -tyrosine hydrazide. 相似文献
106.
107.
A. N. Danilewsky S. Lauer J. Meinhardt K. W. Benz B. Kaufmann R. Hofmann A. Dornen 《Journal of Electronic Materials》1996,25(7):1082-1087
GaSb bulk single crystals with low acceptor concentration were grown from a bismuth solution by the traveling heater method.
The result is isoelectronic doping by Bi which gives a variation of the opto-electronic properties as a function of grown
length as well as a pronounced microscopic segregation. Photoluminescence spectra at 4K show a decrease of the natural acceptor
during growth, which is confirmed by Hall measurements. The electrical properties of this isoelectronic doped GaSb are hole
concentrations and mobilities of NA − ND = 1.7 × 1016 cm−3 and μ = 870 cm2Vs at room temperature and NA-ND = 1 × 1016 cm−3 and μ = 4900 cm2/Vs at 77K, respectively. The lowest p-type carrier concentration measured at 300K is NA − ND = 3.3 × 1015 cm−3 相似文献
108.
A surface of epoxy-impregnated hardened cement paste was investigated using a novel atomic force microscopy (AFM) imaging mode that allows for the quantitative mapping of the local elastic modulus. The analyzed surface was previously prepared using focussed ion beam milling. The same surface was also characterized by electron microscopy and energy-dispersive X-ray spectroscopy.We demonstrate the capability of this quantitative nanomechanical mapping to provide information on the local distribution of the elastic modulus (from about 1 to about 100 GPa) with a spatial resolution in the range of decananometers, that corresponds to that of low-keV back-scattered electron imaging. Despite some surface roughness which affects the measured nanomechanical properties it is shown that topography, adhesion and Young's modulus can be clearly distinguished.The quantitative mapping of the local elastic modulus is able to discriminate between phases in the cement paste microstructure that cannot be distinguished from the corresponding back-scattered electron images. 相似文献
109.
Veronika Kaufmann Siegfrid Scherer Ulrich Kulozik 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,5(42):59-64
Die ESL-Technologie stellt nach der H-Milch eine weitere Entwicklung mit hohem Zusatznutzen in Bezug auf Haltbarkeit und Vorratshaltung
dar, wovon sowohl Handel als auch Verbraucher gleicherma?en profitieren k?nnen. Im Vergleich zum herk?mmlich pasteurisierten
Produkt bringt das ESL-Konzept entscheidende Vorteile hinsichtlich der Haltbarkeit der Milch mit sich, wirkt sich dabei aber
kaum oder nur geringfügig auf die für den Verbraucher entscheidenden bzw. wertrelevanten Produkteigenschaften aus. ESL-Produkte
sind in diesem Sinne also nicht nur „l?nger haltbar”, sondern unserer Einsch?tzung nach auch „l?nger frisch”. Dass gerade
die Produktcharakteristika der ESL-Milch den Wünschen der Verbraucher entgegenkommen, zeigt sich an der stetig steigenden
Nachfrage nach diesen Produkten und dem damit einhergehenden Absatzrückgang von herk?mmlich pasteurisierter Frischmilch. Die
Verbraucher haben also durch ihr Kaufverhalten in den letzten Jahren bereits deutlich gemacht, dass sie der ESL-Milch durchaus
positiv gegenüberstehen und sich mit diesem Produktkonzept keineswegs „get?uscht” fühlen, was die hier zusammengefassten Fakten
eindeutig untermauern. 相似文献
110.
Klaus-Peter Hinz Raimund Kaufmann Bernhard Spengler 《Aerosol science and technology》2013,47(4):233-242
ABSTRACT The instrumental setup used for simultaneous bipolar ion detection in on-line single-particle analysis by laser mass spectrometry is described. Particle size calibration has been performed using aerodynamic time-of-flight techniques. Mass spectra of several hundred ambient particles with aerodynamic diameters of 0.8 μm have been evaluated for statistical classification (Principal Components Analysis [PCA]) in order to identify main chemical components of the prominent particle classes. 相似文献