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71.
72.
介绍了德国HA公司最新研制的CORDIS无机粘结剂的组成与性能以及应用中的问题。  相似文献   
73.
74.
Cross Magnetron Effect and ITO Film Deposition The large area deposition of TCO films requires a strictly homogeneous lateral distribution of the process parameters at the substrate position. In view of that, Cross Corner Effect (in case of a single magnetron source) and Cross Magnetron Effect (for dual magnetrons) can cause problems. Measurements confirm a distinct influence of these effects on the functional properties of indium tin oxide films. The effect will be discussed in terms of the concentration of the dissociated oxygen in the process gas, which depends on the plasma properties and the oxygen partial pressure.  相似文献   
75.
Owing to their excellent high temperature and oxidation resistance, non-oxide polymer-derived silicon-based ceramics are suitable for applications in hot and corrosive environments. The metal (Fe, Co)-containing pre-ceramic compounds combine the processability of organic polymers with the physical and chemical characteristics of the metallic component. In this study, we will introduce two different routes to embed metal particles in a SiCN ceramic matrix, derived from the commercially available polysilazane Ceraset®. (1). Mixing and milling of metal powders (Fe, Co) with pre-crosslinked polysilazane followed by pyrolysis at 1100 °C. (2). Chemical reaction between metal carbonyl compounds, namely Fe(CO)5 and Co2(CO)8, with pure polyorganosilazane followed by pyrolysis at 1100 °C. Both synthetic routes will be discussed on two particular examples, iron- and cobalt-containing samples as well as their resulting different microstructures with respect to their magnetic properties. The phases and microstructures of the metal–SiCN composites were investigated in terms of X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with EDX, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and magnetometer. Upon annealing in argon at 1100 °C, the crosslinked polysilazane blended with iron powder possesses a high saturation magnetization of about ~57 emu/g and exhibits good ferromagnetic behaviour in comparison to the one blended with cobalt. The magnetic measurements were performed within the temperature range 65–300 K.  相似文献   
76.
77.
Magnetic Resonance Materials in Physics, Biology and Medicine - Alternative versions of echo-planar imaging (EPI) sequences with standard spin echo (SE) or stimulated echo acquisition mode (STEAM)...  相似文献   
78.

Objective

Proton density (PD) mapping requires correction for the receive profile (RP), which is frequently performed via bias-field correction. An alternative RP-mapping method utilizes a comparison of uncorrected PD-maps and a value ρ(T1) directly derived from T1-maps via the Fatouros equation. This may be problematic in multiple sclerosis (MS), if respective parameters are only valid for healthy brain tissue. We aimed to investigate whether the alternative method yields correct PD values in MS patients.

Materials/methods

PD mapping was performed on 27 patients with relapsing-remitting MS and 27 healthy controls, utilizing both methods, yielding reference PD values (PDref, bias-field method) and PDalt (alternative method).

Results

PDalt-values closely matched PDref, both for patients and controls. In contrast, ρ(T1) differed by up to 3 % from PDref, and the voxel-wise correlation between PDref and ρ(T1) was reduced in a patient subgroup with a higher degree of disability. Still, discrepancies between ρ(T1) and PDref were almost identical across different tissue types, thus translating into a scaling factor, which cancelled out during normalization to 100 % in CSF, yielding a good agreement between PDalt and PDref.

Conclusion

RP correction utilizing the auxiliary parameter ρ(T1) derived via the Fatouros equation provides accurate PD results in MS patients, in spite of discrepancies between ρ(T1) and actual PD values.
  相似文献   
79.
Korn  Ralf  Yilmaz  Bilgi 《Computational Economics》2022,60(1):281-303
Computational Economics - We present a new modeling approach for house price movements as a consequence of the trading behavior of market agents. In our modeling approach, all agents are assumed to...  相似文献   
80.
Zusammenfassung The importance of the Internet for job procurement is increasing for the reason that three quarters of the people in the employment age are online. On the other hand because ever more companies are publishing their job offers on the Web. However, due to the large number of openings published online it is almost impossible for job seekers and job portals to gain an overview of the entire employment market. Since job offers lack semantically meaningful annotations, the search and integration into databases are made highly difficult. Applying Semantic Web technologies to the e-recruitment process provides advantages for all participants in the market. In this paper we describe a method for analysing the domain-specific language of an application domain. We use this method to describe the e-recruitment process and the necessary ontologies for annotating job offers and job applications. In conclusion, we present the prototypical implementation of the scenario based on Semantic Web, especially semantic matching.  相似文献   
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