2,640 research outputs found
MAX-DOAS measurements of tropospheric NO and HCHO in Munich and the comparison to OMI and TROPOMI satellite observations
We present two-dimensional scanning Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations of nitrogen dioxide (NO) and formaldehyde (HCHO) in Munich. Vertical columns and vertical distribution profiles of aerosol extinction coefficient, NO and HCHO are retrieved from the 2D MAX-DOAS observations. The measured surface aerosol extinction coefficients and NO mixing ratios derived from the retrieved profiles are compared to in situ monitoring data, and the surface NO mixing ratios show a good agreement with in situ monitoring data with a Pearson correlation coefficient (R) of 0.91. The aerosol optical depths (AODs) show good agreement as well (R = 0.80) when compared to sun photometer measurements. Tropospheric vertical column densities (VCDs) of NO and HCHO derived from the MAX-DOAS measurements are also used to validate Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI) satellite observations. Monthly averaged data show a good correlation; however, satellite observations are on average 30 % lower than the MAX-DOAS measurements. Furthermore, the MAX-DOAS observations are used to investigate the spatiotemporal characteristic of NO and HCHO in Munich. Analysis of the relations between aerosol, NO and HCHO shows higher aerosol-to-HCHO ratios in winter, which reflects a longer atmospheric lifetime of secondary aerosol and HCHO during winter. The analysis also suggests that secondary aerosol formation is the major source of these aerosols in Munich
Broadband enhanced transmission through the stacked metallic multi-layers perforated with coaxial annular apertures
This paper theoretically and experimentally presents a first report on
broadband enhanced transmission through stacked metallic multi-layers
perforated with coaxial annular apertures (CAAs). Different from previous
studies on extraordinary transmission that occurs at a single frequency, the
enhanced transmission of our system with two or three metallic layers can span
a wide frequency range with a bandwidth about 60% of the central frequency. The
phenomena arise from the excitation and hybridization of guided resonance modes
in CAAs among different layers. Measured transmission spectra are in good
agreement with calculations semi-analytically resolved by modal expansion
method.Comment: 9 pages,4 figure
A novel context ontology to facilitate interoperation of semantic services in environments with wearable devices
The LifeWear-Mobilized Lifestyle with Wearables (Lifewear) project attempts to create Ambient Intelligence (AmI) ecosystems by composing personalized services based on the user information, environmental conditions and reasoning outputs. Two of the most important benefits over traditional environments are 1) take advantage of wearable devices to get user information in a nonintrusive way and 2) integrate this information with other intelligent services and environmental sensors. This paper proposes a new ontology composed by the integration of users and services information, for semantically representing this information. Using an Enterprise Service Bus, this ontology is integrated in a semantic middleware to provide context-aware personalized and semantically annotated services, with discovery, composition and orchestration tasks. We show how these services support a real scenario proposed in the Lifewear project
Ricin B chain targeted to the endoplasmic reticulum of tobacco protoplasts is degraded by a CDC48- and vacuole-independent mechanism
The B chain of ricin was expressed and delivered to the endoplasmic
reticulum of tobacco protoplasts where it disappeared
with time in a manner consistent with degradation. This turnover
did not occur in the vacuoles or upon secretion. Indeed,
several lines of evidence indicate that, in contrast to the turnover
of endoplasmic reticulum-targeted ricin A chain in the
cytosol, the bulk of expressed ricin B chain was degraded in the
secretory pathway
The Secretion of Streptomyces monbaraensis Transglutaminase From Lactococcus lactis and Immobilization on Porous Magnetic Nanoparticles
Microbial transglutaminase (MTG) from Streptomyces mobaraensis is an important
enzyme widely applied in food processing for the improvement of protein properties
by catalyzing the cross-linking of proteins. In this work we aimed at improving
the production and enabling an easy and efficient purification process from culture
supernatants. Thus, recombinant vectors, with either a constitutive promoter (Pp5) or
an inducible promoter (PnisA), controlling the expression of the MTG gene fused to the
signal peptide of Usp45 (SPusp45) were constructed and then expressed in Lactococcus
lactis. After purification, 43.5 +/- 0.4 mg/L mature MTG-6His was obtained. It displayed
27.6 +/- 0.5 U/mg enzymatic activity cross-linking soy protein isolate effectively. The
purified mature MTG was immobilized with magnetic porous Fe3O4 nanoparticles,
which improved its activity up to 29.1 +/- 0.4 U/mg. The immobilized MTG maintained
67.2% of the initial activity after being recycled for 10 times. The high production
and secretion of functional S. mobaraensis MTG from L. lactis and the magnetic
immobilized MTG-6His onto Fe3O4 nanoparticles reported in this study would have
potential industrial applications.This study was granted by the National Key Research and
Development Program of China (2018YFD0400600 and
2018YFD0400400), Key Scientific and Technological Project of
Anhui Province of China (Nos. 17030701014 and 18030701146),
Anhui Provincial Natural Science Foundation (1708085QC65),
the Open Fund of State Key Laboratory of Tea Plant Biology and
Utilization (SKLTOF20180107), and China Postdoctoral Science
Foundation (2019M651013)
The effect of oxygen stoichiometry on electrical transport and magnetic properties of La0.9Te0.1MnOy
The effect of the variation of oxygen content on structural, magnetic and
transport properties in the electron-doped manganites La0.9Te0.1MnOy has been
investigated. All samples show a rhombohedral structure with the space group .
The Curie temperature decreases and the paramagnetic-ferromagnetic (PM-FM)
transition becomes broader with the reduction of oxygen content. The
resistivity of the annealed samples increases slightly with a small reduction
of oxygen content. Further reduction in the oxygen content, the resistivity
maximum increases by six orders of magnitude compared with that of the
as-prepared sample, and the r(T) curves of samples with y = 2.86 and y = 2.83
display the semiconducting behavior () in both high-temperature PM phase and
low-temperature FM phase, which is considered to be related to the appearance
of superexchange ferromagnetism (SFM) and the localization of carriers. The
results are discussed in terms of the combined effects of the increase in the
Mn2+/(Mn2++Mn3+) ratio, the partial destruction of double exchange (DE)
interaction, and the localization of carriers due to the introduction of oxygen
vacancies in the Mn-O-Mn network.Comment: 20 pages, 8 figure
Charge Transport in Manganites: Hopping Conduction, the Anomalous Hall Effect and Universal Scaling
The low-temperature Hall resistivity \rho_{xy} of La_{2/3}A_{1/3}MnO_3 single
crystals (where A stands for Ca, Pb and Ca, or Sr) can be separated into
Ordinary and Anomalous contributions, giving rise to Ordinary and Anomalous
Hall effects, respectively. However, no such decomposition is possible near the
Curie temperature which, in these systems, is close to metal-to-insulator
transition. Rather, for all of these compounds and to a good approximation, the
\rho_{xy} data at various temperatures and magnetic fields collapse (up to an
overall scale), on to a single function of the reduced magnetization
m=M/M_{sat}, the extremum of this function lying at m~0.4. A new mechanism for
the Anomalous Hall Effect in the inelastic hopping regime, which reproduces
these scaling curves, is identified. This mechanism, which is an extension of
Holstein's model for the Ordinary Hall effect in the hopping regime, arises
from the combined effects of the double-exchange-induced quantal phase in
triads of Mn ions and spin-orbit interactions. We identify processes that lead
to the Anomalous Hall Effect for localized carriers and, along the way, analyze
issues of quantum interference in the presence of phonon-assisted hopping. Our
results suggest that, near the ferromagnet-to-paramagnet transition, it is
appropriate to describe transport in manganites in terms of carrier hopping
between states that are localized due to combined effect of magnetic and
non-magnetic disorder. We attribute the qualitative variations in resistivity
characteristics across manganite compounds to the differing strengths of their
carrier self-trapping, and conclude that both disorder-induced localization and
self-trapping effects are important for transport.Comment: 29 pages, 20 figure
Measurements of psi(2S) decays to octet baryon-antibaryon pairs
With a sample of 14 million psi(2S) events collected by the BESII detector at
the Beijing Electron Positron Collider (BEPC), the decay channels psi(2S)->p
p-bar, Lambda Lambda-bar, Sigma0 Sigma0-bar, Xi Xi-bar are measured, and their
branching ratios are determined to be (3.36+-0.09+-0.24)*10E-4,
(3.39+-0.20+-0.32)*10E-4, (2.35+-0.36+-0.32)*10E-4, (3.03+-0.40+-0.32)*10E-4,
respectively. In the decay psi(2S)->p p-bar, the angular distribution parameter
alpha is determined to be 0.82+-0.17+-0.04.Comment: 8 pages, 8 figure
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