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71.
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
72.
A BABANEJHAD M HASHEMI Y RAHMATALLAHPUR SH A NOZAD 《Bulletin of Materials Science》2012,35(4):561-566
The present work aims to study effect of lactic acid concentration as complexing agent on surface roughness and nucleation morphology of electroless N?CP deposition. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been used to study nucleation morphology and surface roughness of deposition. Deposition process started at some initial priority growing centres independently distributed on the substrate. We found that the morphology and surface roughness of deposition strongly depends on the complexing agent concentration. Morphology of initial deposited centres with no concentration of lactic acid was in coniform structure. By increasing the complexing agent concentration, the structure of initial growing centres changed from coniform to nodular shape and the surface roughness of depositions decreased. 相似文献
73.
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
74.
介绍了真空缓冷炉渣的工艺矿物学特性。试验研究结果表明,该炉渣属于中等可碎性偏难,硬度系数在8 ̄16之间,在磨矿细度为-0.016mm占89%时,粗、扫选抛尾粗精矿再磨再选,以Z-200、SN-9和丁胺为混合捕收剂,最终得到铜精矿产率为4.59%,精矿含铜23.48%,含金5.8g/t,铜回收率为83.70%;尾矿含铜0.22%,含金0.18g/t。 相似文献
75.
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
76.
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
77.
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
78.
79.
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
80.
H凹陷三叠系小泉沟群地震相分析 总被引:1,自引:0,他引:1
在中国西部许多陆相盆地中,发育了多种各样的砂岩储集体,这些砂体在不同的沉积环境、不同的相带中有规律地分布着。文中对西部某盆地H凹陷三叠系小泉沟群地震相和沉积相进行了较详细的研究;分析了该组的岩性特征、地震相特征和剖面沉积相特征,指出了各种沉积相中的主要砂体类型及有利的含油气相带。 相似文献