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971.
Recently, Nation et al. confirmed that fluxes of Hawking radiation energy and entropy from a black hole can be regarded as a one-dimensional (1D) non-equilibrium Landauer transport process. Their work can be extended to background space-times with gauge potential. The result shows that the energy flux of charged particles, which is shown to be equal to the energy–momentum tensor flux, contains not only the contribution of thermal flux but also that of particle flux. It is found that the charge can also be transported by the 1D quantum channel. Moreover, the entropy production rate is also investigated, which is shown to be larger than the case without chemical potential. 相似文献
972.
Bin Zhao 《Journal of Thermal Analysis and Calorimetry》2012,107(1):387-393
In order to study the temperature changing rule of the crude oil in the storage tank, the wavelet finite element method, the
traditional finite element method and the test were used to carry out the numerical simulation. Firstly, the thermal wavelet
finite element was put forward established based on thermal finite element theory and the wavelet theory. And the computational
model and three boundary conditions were established. And then the temperature changing rule of the crude oil in the storage
tank in 24 h for three boundary conditions was obtained by using three methods, and the results showed that the wavelet finite
element method had advantages in the numerical analysis of the temperature changing rule of the crude oil in the storage.
And then the temperature distribution rule of the crude oil in the storage tank under different conditions in 5 h was obtained.
And the temperature changing mechanism of the crude oil was summarized finally. 相似文献
973.
Flexible conductive polymer hydrogels are unique material that synergize the features of conductive polymers and hydrogels. They are excellent candidates for the flexible supercapacitor electrodes. In this paper, flexible conductive polymer hydrogels were prepared with poly(vinyl alcohol) as soft skeleton through cyclic freezing-thawing method. Firstly, phytic acid-doped polyaniline with crosslinked network was prepared using phytic acid as the dopant and crosslinking agents. Hydrogels with interpenetrating binary network nanostructure were then formed by freezing-thawing method. The interpenetrating binary network structure endowed the hydrogel reliable mechanical properties with decent flexibility and compressive strength of 3.64 MPa. More importantly, this unique structure enable them to maintain highly specific capacitance (314 F/g at the current density of 0.5 A/g). 相似文献
974.
975.
Chao Dou Xili Jing Shuguang Li Junjun Wu Qingbo Wang 《Optical and Quantum Electronics》2018,50(6):255
The characteristics of a novel dual-core photonic crystal fiber are investigated. In the center of photonic crystal fiber, an energy transmission channel is introduced. The optimized photonic crystal fiber can be used for polarization splitter, which has a short length and low loss. 相似文献
976.
The search for and study of exotic quantum states in novel low-dimensional quantum materials have triggered extensive research in recent years. Here, we systematically study the electronic and magnetic structures in the newly discovered two-dimensional quantum material C3N within the framework of density functional theory. The calculations demonstrate that C3N is an indirect-band semiconductor with an energy gap of 0.38 eV, which is in good agreement with experimental observations. Interestingly, we find van Hove singularities located at energies near the Fermi level, which is half that of graphene. Thus, the Fermi energy easily approaches that of the singularities, driving the system to ferromagnetism, under charge carrier injection, such as electric field gating or hydrogen doping. These findings not only demonstrate that the emergence of magnetism stems from the itinerant electron mechanism rather than the effects of local magnetic impurities, but also open a new avenue to designing field-effect transistor devices for possible realization of an insulator–ferromagnet transition by tuning an external electric field. 相似文献
977.
978.
Yuan Hu Brad Sherborne Tai-Sung Lee David A. Case Darrin M. York Zhuyan Guo 《Journal of computer-aided molecular design》2016,30(7):533-539
In drug discovery, protonation states and tautomerization are easily overlooked. Through a Merck–Rutgers collaboration, this paper re-examined the initial settings and preparations for the Thermodynamic Integration (TI) calculation in AMBER Free-Energy Workflows, demonstrating the value of careful consideration of ligand protonation and tautomer state. Finally, promising results comparing AMBER TI and Schrödinger FEP+ are shown that should encourage others to explore the value of TI in routine Structure-based Drug Design. 相似文献
979.
Kätlin Kaare Ivar Kruusenberg Maido Merisalu Leonard Matisen Väino Sammelselg Kaido Tammeveski 《Journal of Solid State Electrochemistry》2016,20(4):921-929
Manganese phthalocyanine (MnPc) and copper phthalocyanine (CuPc)-modified electrodes were prepared using multi-walled carbon nanotubes (MWCNTs) as a support material. The catalyst materials were heat treated at four different temperatures to investigate the effect of pyrolysis on the oxygen reduction reaction (ORR) activity of these electrocatalysts. The MWCNT to metal phthalocyanine ratio was varied. Scanning electron microscopy (SEM) was employed to visualise the surface morphology of the electrodes and the x-ray photoelectron spectroscopic (XPS) study was carried out to analyse the surface composition of the most active catalyst materials. The ORR was studied in 0.1 M KOH solution employing the rotating disk electrode (RDE) method. Glassy carbon (GC) electrodes were modified with carbon nanotube-supported metal phthalocyanine catalysts using Tokuyama AS-4 ionomer. The RDE results revealed that the highest electrocatalytic activity for ORR was achieved upon heat treatment at 800 °C. CuPc-derived catalyst demonstrated lower catalytic activity as compared to the MnPc-derived counterpart, which is in good agreement with previous literature, whereas the activity of MnPc-based catalyst was higher than that reported earlier. 相似文献
980.
Fangyuan Gao Quanqing Zhang Xiuqin Li Qinghe Zhang Ting Mao Yong Lu Weibing Zhang Hongmei Li 《Accreditation and quality assurance》2016,21(6):395-401
In this study, a standard addition–isotope dilution mass spectrometry (SA-IDMS) method for quantification of endogenous progesterone in milk has been described. The method validation results, linearity, limits of detection and quantification, recovery and uncertainty were fit for the purpose of assigning reference mass fractions to proficiency testing schemes. The developed technique was compared to the isotope dilution mass spectrometry (IDMS) method already existing in the laboratory. Analytical results of two milk samples were (1.377 ± 0.048) μg/kg and (4.457 ± 0.155) μg/kg by SA-ID-LC/MS method, while the results were (1.355 ± 0.019) μg/kg and (4.359 ± 0.059) μg/kg by ID-LC/MS, respectively. Since SA-IDMS was an effective quantitative method that overcame matrix effect, similar quantitative results from IDMS and SA-IDMS indicated that the quantification of progesterone in milk was barely influenced by matrix. Both IDMS and SA-IDMS could be used to assign reference mass fractions to progesterone in milk inter-laboratory proficiency testing schemes. 相似文献