Optical absorption properties of Ge2–44 and P-doped Ge nanoparticles

The optical absorption properties of non-crystalline and crystalline Ge nanoparticles with the sizes from ∼2.5 to 15 Å have been studied at the B3LYP/6-31G level using time-dependent density functional theory. Hydrogen passivation and phosphorus doping on some selected Ge nanoparticles were also calculated. With the increase of cluster size, the optical absorption spectra of the non-crystalline Ge nanoparticles change from many peaks to a continuous broad band and at the same time exhibit a systematic red-shift. Doping phosphorus also causes the absorption spectra to shift toward the lower energy region for both non-crystalline and crystalline Ge nanoparticles. The non-crystalline Ge nanoparticles are found to have stronger absorption in the visible region in comparison with the crystalline ones, regardless phosphorus doping

EUCLIA - Exploring the UV/optical continuum lag in active galactic nuclei. I. a model without light echoing

The tight inter-band correlation and the lag-wavelength relation among UV/optical continua of active galactic nuclei have been firmly established. They are usually understood within the widespread reprocessing scenario, however, the implied inter-band lags are generally too small. Furthermore, it is challenged by new evidences, such as the X-ray reprocessing yields too much high frequency UV/optical variations as well as it fails to reproduce the observed timescale-dependent color variations among {\it Swift} lightcurves of NGC 5548. In a different manner, we demonstrate that an upgraded inhomogeneous accretion disk model, whose local {\it independent} temperature fluctuations are subject to a speculated {\it common} large-scale temperature fluctuation, can intrinsically generate the tight inter-band correlation and lag across UV/optical, and be in nice agreement with several observational properties of NGC 5548, including the timescale-dependent color variation. The emergent lag is a result of the {\it differential regression capability} of local temperature fluctuations when responding to the large-scale fluctuation. An average speed of propagations as large as $\gtrsim 15\%$ of the speed of light may be required by this common fluctuation. Several potential physical mechanisms for such propagations are discussed. Our interesting phenomenological scenario may shed new light on comprehending the UV/optical continuum variations of active galactic nuclei.Comment: 18 pages, 8 figures. ApJ accepted. Further comments are very welcome

Study on Law of Personnel Evacuation in Deep Buried Metro Station Based on the Characteristics of Fire Smoke Spreading

AbstractWith the improvement of people's life and the rapid development of urban traffic, the subway has the advantages of convenience and celerity, to a large extent, which greatly eases the traffic congestion phenomenon. With the attendant, the safety of the subway environment becomes vital. Many engineers focus on the study of the fire prevention and safety to escape. In this paper, a comprehensive study on the fire smoke spreading and the evacuation of the people in the deep buried metro model is carried out. First, the deep buried metro model is modeled on the STEPS software, and the personnel evacuation rule is obtained. According to the evacuation situation, the corresponding fire smoke monitoring points are built in the fire scenario which is set up on FDS+Evac software. Then, FDS+Evac program is used to simulate the evacuation in a fire scenario. It has not only analyzed the real time effect that the characteristics of fire smoke spread have on the personnel evacuation, but also improved the accuracy of the subway fire safety evaluation

Identification of metabolites of gardenin A in rat liver microsomes using ultra-high performance liquid chromatography coupled with linear ion-trap Orbitrap mass spectrometry

Purpose: To identify the metabolites of gardenin A (GA) in rat liver microsomes (RLMs) using ultra-high performance liquid chromatography coupled with linear ion-trap Orbitrap mass spectrometry (UHPLCLTQ- Orbitrap).Methods: The sample was prepared by incubating GA (100 μg/mL) with RLMs (0.5 mg/mL) for 8 h. Then 5 μL of the sample was injected into UHPLC-LTQ- orbitrap mass spectrometer. The metabolites of GA were tentatively identified based on accurate mass measurements, fragmentation patterns, chromatographic retention times, and bibliography data.Results: A total of 12 metabolites were detected and identified. Based on their  structures, the main reactions in the metabolism of GA are de-methoxylation and de-methylation.Conclusion: This is the first report on in vitro metabolites of GA. These results are considered very helpful for better comprehension of the metabolism of GA and its pharmacological effects.Keywords: Gardenin A, Metabolites, UHPLC-LTQ-Orbitrap, Rat Liver microsome

An intrinsic link between long-term UV/optical variations and X-ray loudness in quasars

Observations have shown that UV/optical variation amplitude of quasars depend on several physi- cal parameters including luminosity, Eddington ratio, and likely also black hole mass. Identifying new factors which correlate with the variation is essential to probe the underlying physical processes. Combining ~ten years long quasar light curves from SDSS stripe 82 and X-ray data from Stripe 82X, we build a sample of X-ray detected quasars to investigate the relation between UV/optical variation amplitude ($\sigma_{rms}$) and X-ray loudness. We find that quasars with more intense X-ray radiation (com- pared to bolometric luminosity) are more variable in UV/optical. Such correlation remains highly significant after excluding the effect of other parameters including luminosity, black hole mass, Ed- dington ratio, redshift, rest-frame wavelength (i.e., through partial correlation analyses). We further find the intrinsic link between X-ray loudness and UV/optical variation is gradually more prominent on longer timescales (up to 10 years in the observed frame), but tends to disappear at timescales < 100 days. This suggests a slow and long-term underlying physical process. The X-ray reprocessing paradigm, in which UV/optical variation is produced by a variable central X-ray emission illuminating the accretion disk, is thus disfavored. The discovery points to an interesting scheme that both the X-ray corona heating and UV/optical variation is quasars are closely associated with magnetic disc turbulence, and the innermost disc turbulence (where corona heating occurs) correlates with the slow turbulence at larger radii (where UV/optical emission is produced).Comment: 9 pages, 4 figures, 1 table, accepted by Ap

5-(1H-Tetra­zol-5-yl)-1H-indole monohydrate

In the title compound, C9H7N5·H2O, the inter­planar angles between the benzene and tetra­zole rings and between the benzene and imidazole rings are 8.71 (3) and 1.32 (2)°, respectively. In the crystal, strong N—H⋯N hydrogen bonds link the organic 5-(1H-tetra­zol-5-yl)-1H-indole mol­ecules into chains extended along the b axis. The chains are further inter­connected into layers parallel to (100) via strong O—H⋯N and N—H⋯O hydrogen bonds. Furthermore, the layers are inter­connected via strong O—H⋯N hydrogen bonds. Moreover, cohesion between the layers is provided by the π–π inter­actions between the imidazole, tetra­zole and benzene rings with centroid–centroid distances of 3.766 (2), 3.832 (2) and 3.733 (2) Å

Transitional care for patients with chronic obstructive pulmonary disease

AbstractObjectivesTo observe the effects of transitional care on the quality of life of chronic obstructive pulmonary disease (COPD) patients.MethodsA total of 114 COPD patients were recruited from the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China and divided equally into an intervention group and control group. Following discharge, patients from the intervention group recieved three-months intervention in addition to regular nursing care, while control group patients received regular nursing care only. Patients' quality of life was measured using the St. George's respiratory questionnaire (SGRQ), the 12-item General Health Questionnaire (GHQ-12) and body mass index (BMI).ResultsThe symptoms section score, the activity section score, the impacts section score, the total score and the rate of mental disorders were significantly changed after the intervention while there was no statistical difference in BMI between groups.ConclusionsTransitional care can improve health-related quality of life in COPD patients who have recently suffered an exacerbation