2,118 research outputs found
Fermions tunneling from higher-dimensional charged AdS black hole in dRGT massive gravity within modified dispersion relation
The tunneling behavior of fermions with half-integral spin from a higher
dimensional charged anti-de Sitter (AdS) black hole in de Rham, Gabadadze and
Tolley (dRGT) massive gravity is investigated via a modified Hamilton-Jacobi
equation. The results demonstrate that the modified thermodynamic quantities
not only are related to the properties of the higher dimensional charged AdS
black hole in dRGT massive gravity but also depend on the parameter ,
the coupling constant and the mass of emitted particles . In
addition, the modified Hawking temperature is higher than the original
temperature; hence, the effect of MDR can significantly enhance the evolution
of the black hole. Besides, our results can be verified using the modified
Stefan-Boltzmann law.Comment: 7 pages, corrected typo
Biomass-derived three-dimensional porous N-doped carbonaceous aerogel for efficient supercapacitor electrodes
Functionalized carbonaceous materials with hierarchical structure and developed porosity are highly desired in energy storage and conversion fields. In this work, a facile and scalable hydrothermal methodology was established to synthesise three-dimensional (3D) N-doped carbonaceous aerogels using biomass-based starting materials and polypyrrole as N-source. The effect of different calcination temperatures on the structural properties, type and content of N-species and electrochemical performance of the 3D N-doped carbonaceous aerogels were uncovered. Thanks to the combinatorial effect of the appropriate N content and porous structure, the obtained samples exhibited excellent electrochemical performance, in particular, an outstanding specific capacitance of 281.0 F g-1 achieved on the sample calcined at 600 °C. This methodology offers a new fabrication strategy to prepare nanoscale carbonaceous materials with desirable morphology and hierarchical architecture of great potentials for the applications in energy fields
A Two-Dimensional CA Traffic Model with Dynamic Route Choices Between Residence and Workplace
The Biham, Middleton and Levine (BML) model is extended to describe dynamic
route choices between the residence and workplace in cities. The traffic
dynamic in the city with a single workplace is studied from the velocity
diagram, arrival time probability distribution, destination arrival rate and
convergence time. The city with double workplaces is also investigated to
compared with a single workplace within the framework of four modes of urban
growth. The transitional region is found in the velocity diagrams where the
system undergoes a continuous transition from a moving phase to a completely
jamming phase. We perform a finite-size scaling analysis of the critical
density from a statistical point of view and the order parameter of this
jamming transition is estimated. It is also found that statistical properties
of urban traffic are greatly influenced by the urban area, workplace area and
urban layout.Comment: 18 pages, 13 figure
Simulation of adaptive circular array for CDMA systems
In this thesis, we study the performance of adaptive Uniformly Spaced Circular Array (UCA) and Uniformly Spaced Linear Array (ULA) utilized in the base station of CDMA systems. In these systems, the desired signal becomes much stronger than the interference signals after chip correlation by a factor of the processing gain. Further, simple blind algorithms and the real-time implementation can be applied to improve bit error rate in various interference scenario. The performance of several algorithms is compared in AWGN channel, Rayleigh Flat Fading channel, and Frequency Selective Fading channel considering angle spread, phase errors and mobile tracking. In wireless communications, propagation effects of the transmitted signals result in delay spread, angle spread, Doppler spread and multipath in mobile radio channel. Different antenna array geometries may cause different responses to the received signals. Our study shows that the UCA is less sensitive to the angle spread than the ULA does, consequently the UCA exhibits better performance than the ULA in the multipath environment with angle spread, which is almost certainly the case in the uplink of CDMA communication systems
Clinical observation on pathologic myopia CNV treated with intravitreal bevacizumab
AIM: To evaluate the efficacy and safety of intravitreal bevacizumab(Avastin)for choroidal neovascularization(CNV)in pathologic myopia(PM)by including optical coherence tomography(OCT), fluorescein angiography(FFA)and best-corrected visual acuity(BCVA). METHODS: Totally 42 eyes in 41 patients with PM CNV were divided into 2 groups randomly, experimental group(n=22)were assigned to receive intravitreal bevacizumab injections and take fufangxueshuantong capsule; control group(n=20)just took fufangxueshuantong capsule. Subjects were followed up every month after treatment. The efficacy and safety of two group were compared by ophthalmic evaluations including OCT, FFA, and BCVA. RESULTS: BCVA: BCVA in two groups was improved after 12 months. The mean number of treatments per eye, experimental group was 4.23±2.02 and control group was 1.95±1.90. There was significant difference(P<0.005). OCT: Before and after 12 months central foveal thickness(CFD)for two groups were thin,and the mean value in experimental group was 43.41±40.39μm and in control group was 22.65±20.79μm, there was significant difference(P<0.05); FFA: In experimental group CNV was completely disappeared in 20 eyes(91%), persistent in 2 eyes(9%); the control group CNV was completely disappeared in 12 eyes(60%), persistent in 8 eyes(40%). There was significant difference(P<0.05). CONCLUSION: Intravitreal bevacizumab are safe and effective treatment for most patients of CNV in PM
Assessment of the spatial and temporal variations of water quality for agricultural lands with crop rotation in China by using a HYPE model
Many water quality models have been successfully used worldwide to predict nutrient losses from anthropogenically impacted catchments, but hydrological and nutrient simulations with little data are difficult considering the transfer of model parameters and complication of model calibration and validation. This study aims (i) to assess the performance capabilities of a new and relatively more advantageous model-hydrological predictions for the environment (HYPE) to simulate stream flow and nutrient load in ungauged agricultural areas by using a multi-site and multi-objective parameter calibration method and (ii) to investigate the temporal and spatial variations of total nitrogen (TN) and total phosphorous (TP) concentrations and loads with crop rotation using the model for the first time. A parameter estimation tool (PEST) was used to calibrate parameters, which shows that the parameters related to the effective soil porosity were most sensitive to hydrological modeling. N balance was largely controlled by soil denitrification processes, whereas P balance was influenced by the sedimentation rate and production/decay of P in rivers and lakes. The model reproduced the temporal and spatial variations of discharge and TN/TP relatively well in both calibration (2006–2008) and validation (2009–2010) periods. The lowest NSEs (Nash-Suttclife Efficiency) of discharge, daily TN load, and daily TP load were 0.74, 0.51, and 0.54, respectively. The seasonal variations of daily TN concentrations in the entire simulation period were insufficient, indicated that crop rotation changed the timing and amount of N output. Monthly TN and TP simulation yields revealed that nutrient outputs were abundant in summer in terms of the corresponding discharge. The area-weighted TN and TP load annual yields in five years showed that nutrient loads were extremely high along Hong and Ru rivers, especially in agricultural lands
Bis(2,6-dichloroÂbenzÂyl)selane
The title molÂecule, C14H10Cl4Se, features a selenide bridge between two dichloroÂbenzyl units. The dihedral angle between the two benzene rings is 107.9 (16)°. In the crystal, weak π–π face-to-face aromatic interÂactions are observed [centroid–centroid distance between two adjacent (but crystallographically different) phenyl rings = 3.885 (5) Å], providing some packing stability. Short Cl⋯Cl contacts of 3.41 (2) Å are observed
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