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1.
This paper reveals the state of the technology in both contaminant wear in fluid components and fluid filtration. Through the use of graphical aids, the fundamental relationship influencing contamination control is disclosed. This presentation will show the correlation of filter performance and contaminant ingression on the service life of fluid systems. 相似文献
2.
de Oliveira Passos Marcelo Gonzalez Priscila Lujan Tessmann Mathias Schneid de Abreu Pereira Uhr Daniel 《Scientometrics》2022,127(10):5841-5862
Scientometrics - We use some modern scientometrics tools to detect which articles written in co-authorship are the most influential in the finance theory literature from 1896 to 2006. To develop a... 相似文献
3.
Faria CB Abe CA da Silva CN Tessmann DJ Barbosa-Tessmann IP 《International journal of molecular sciences》2012,13(1):115-132
Fusarium verticillioides and Fusarium subglutinans are important fungal pathogens of maize and other cereals worldwide. In this study, we developed PCR-based protocols for the identification of these pathogens targeting the gaoB gene, which codes for galactose oxidase. The designed primers recognized isolates of F. verticillioides and F. subglutinans that were obtained from maize seeds from several producing regions of Brazil but did not recognize other Fusarium spp. or other fungal genera that were either obtained from fungal collections or isolated from maize seeds. A multiplex PCR protocol was established to simultaneously detect the genomic DNA from F. verticillioides and F. subglutinans. This protocol could detect the DNA from these fungi growing in artificially or naturally infected maize seeds. Another multiplex reaction with a pair of primers developed in this work combined with a pre-existing pair of primers has allowed identifying F. subglutinans, F. konzum, and F. thapsinum. In addition, the identification of F. nygamai was also possible using a combination of two PCR reactions described in this work, and another described in the literature. 相似文献
4.
Sebastian Diebold Serdal Ayhan Steffen Scherr Hermann Massler Axel Tessmann Arnulf Leuther Oliver Ambacher Thomas Zwick Ingmar Kallfass 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(12):1250-1267
In medical and personal health systems for vital sign monitoring, contact-free remote detection is favourable compared to wired solutions. For example, they help to avoid severe pain, which is involved when a patient with burned skin has to be examined. Continuous wave (CW) radar systems have proven to be good candidates for this purpose. In this paper a monolithic millimetre-wave integrated circuit (MMIC) based CW radar system operating in the W-band (75–110?GHz) at 96?GHz is presented. The MMIC components are custom-built and make use of 100?nm metamorphic high electron mobility transistors (mHEMTs). The radar system is employing a frequency multiplier-by-twelve MMIC and a receiver MMIC both packaged in split-block modules. They allow for the determination of respiration and heartbeat frequency of a human target sitting in 1?m distance. The analysis of the measured data is carried out in time and frequency domain and each approach is shown to have its advantages and drawbacks. 相似文献
5.
Dammann M. Leuther A. Tessmann A. Massler H. Mikulla M. Weimann G. 《Electronics letters》2005,41(12):699-701
The long-term stability of a 50 nm low-noise metamorphic HEMT technology has been investigated by biased accelerated lifetime tests on both MHEMT devices and two-stage LNAs for W-band applications. The lifetime tests were performed at three channel temperatures, a drain voltage of 1 V and a power density of 0.3 W/mm in air. Based on a -10% degradation of g/sub m max/ failure criterion an activation energy of 1.6 eV and a projected median lifetime of 2.7/spl times/10/sup 6/ h at T/sub ch/=125/spl deg/C were determined. The two-stage LNAs were stressed at a channel temperature of 185/spl deg/C for 4000 h. The S-parameters did not show any significant degradation after 4000 h of stress time if the positive threshold voltage shift was compensated for by a corresponding increase of the gate voltage. The reliability results demonstrate the stable operation of 50 nm MHEMTs and LNAs for W-band applications and beyond. 相似文献
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7.
Daniel Müller Gunnar Scherer Ulrich J. Lewark Hermann Massler Sandrine Wagner Axel Tessmann Arnulf Leuther Thomas Zwick Ingmar Kallfass 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(2):161-176
This paper presents a novel transistor unit cell which is intended to realize compact active switches in the high millimeter-wave frequency range. The unit cell consists of the combination of shunt and common gate transistor within a four-finger transistor cell, achieving gain in the amplifying state as well as good isolation in the isolating state. Gate width-dependent characteristics of the unit cell as well as the design of actual switch implementations are discussed in detail. To verify the concept, two switches, a single pole double throw (SPDT) switch and single pole quadruple throw (SP4T) switch, intended for the WR3 frequency range (220–325 GHz) were manufactured and characterized. The measured gain at 250 GHz is 4.6 and 2.2 dB for the SPDT and SP4T switch, respectively. An isolation of more than 24 dB for the SPDT switch and 12.8 dB for the SP4T switch was achieved. 相似文献
8.
Electronic Markets - Our knowledge on differences in business model characteristics of thriving and failing Multi-Sided Platforms in competitive B2B networks (B2B-MSP) and potential influences of... 相似文献
9.
Astolfi P dos Santos J Schneider L Gomes LB Silva CN Tessmann DJ Del Ponte EM 《International journal of food microbiology》2011,148(3):197-201
Fusarium head blight is a disease of primary concern to small-grain cereals of Brazil, including barley. Its main causal agent, Fusarium graminearum species complex (Fg complex)¸ is able to produce mycotoxins, especially deoxynivalenol (DON) and nivalenol (NIV), that usually contaminate grain. Strains that produce DON may also produce its acetylated derivatives: 3-acetyl-DON (3-ADON) and 15-acetyl-DON (15-ADON). Ninety two isolates were obtained from samplings of barley grain during three years (2007, 2008 and 2009) from several fields in both southern and northern production regions of Rio Grande do Sul state, Brazil. These isolates were examined for polymerase chain-reaction-based (PCR) trichothecene genotype based on the amplification of portions of Tri3 and Tri12. There was no effect of year or region on the proportion of trichothecene genotypes. Overall, 66% of the strains (61/92) were 15-ADON, 4.4% (4/92) were 3-ADON and 29.3% (27/92) were NIV. The overall NIV/DON ratio estimated (0.41) was five times higher than that found in previous studies with strains from wheat grown in the same region. Species identification of nine strains representing the trichothecene genotypes, based on comparisons of DNA sequences of portions of the PHO, RED and URA genes with sequences from curated reference isolates of Fusarium from GenBank, revealed that they belong to F. graminearum sensu stricto (four 15-ADON and one 3-ADON strain), F. meridionale (three NIV strains) and F. austroamericanum (one 3-ADON strain). These results add to the current regional knowledge of trichothecene genotypes and species within the Fg complex affecting barley in the region. 相似文献
10.
Tessmann A. Riessle M. Kudszus S. Massler H. 《Microwave and Wireless Components Letters, IEEE》2004,14(4):145-147
A flip-chip mounted W-band amplifier module with more than 15 dB gain between 82 and 105 GHz has been developed, based on a 0.15 /spl mu/m GaAs PHEMT technology. To predict the influence of the flip-chip transition, an equivalent circuit model of the flip-chip interconnects was developed. Lossy silicon (n-Si) flip-chip carriers were used to successfully minimize parasitic substrate modes and feed back effects. The flip-chip assembled coplanar 94 GHz amplifier MMIC was packaged in a WR-10 waveguide mount, using CPW-to-waveguide transitions realized on quartz substrates. 相似文献