Full-scale Mathematical Model and Simulation of Marine Natural Recirculation Drum-boiler

AbstractThrough some reasonable hypothesis and simplification of conflagation, heat and mass transfer, a full-scale dynamic mathematic model of marine natural recirculation drum-boiler is established by modular modeling method via the basic working elements of objects. The dynamic feature of a certain type natural recirculation drum-boiler was studied by this model as an instance, by contrasting the simulative results and real values, the precision and real-time capability of the developed model was testified. This study was helpful for the performance research, working optimize and control strategy building of various natural recirculation drum-boilers

The influence of protein free calf blood extract eye gel on dry eye after pterygium surgery

AIM: To investigate the influence of protein free calf blood extract eye gel on dry eye after pterygium surgery. <p>METHODS: Thirty six patients(40 eyes)with primary nasal pterygium were enrolled in this study, which were divided into study group and control group randomly, with 20 eyes in each group. All patients received pterygium excision and limbal stem cell autograft surgery and tobramicin dexamethasone eye drops after surgery. Patients of the study group received protein free calf blood extract eye gel while those of the control group received 0.1% sodium hyaluronate eye drops furthermore. Ocular surface disease index(OSDI)questionnaire, tear film break-up time(BUT)and Schirmer's Ⅰ test Ⅰ(SⅠt)were carried before and 3 months after surgery to evaluate the dry eye degree of the patients. <p>RESULTS: There was no statistical difference between the age, gender and size of the pterygium of the study and control groups preoperatively. There was no statistical difference between the OSDI(2.33±1.02 <i>vs</i> 2.32±0.93), BUT(8.80±2.48 <i>vs</i> 8.35±2.28)seconds and SⅠt(4.30±2.30 <i>vs</i> 4.40±2.44)of the two groups preoperatively. There was statistical difference between the OSDI(1.45±0.47 <i>vs</i> 1.81±0.60), BUT(11.20±2.07 <i>vs</i> 9.50±2.40)seconds and SⅠt(8.35±3.13 <i>vs</i> 6.35±2.18)of the two groups 3 months postoperatively, which was also different from that of the preoperative data correspondingly. <p>CONCLUSION: Protein free calf blood extract eye gel could reduce the dry eye after pterygium surgery

Violation of Luttinger's theorem in the simplest doped Mott insulator: Falicov-Kimball model in strong correlation limit

The Luttinger's theorem has long been taken as the key feature of Landau's Fermi liquid, which signals the presence of quasiparticles. Here, by the unbiased Monte Carlo method, violation of Luttinger's theorem is clearly revealed in the Falicov-Kimball (FK) model, indicating the robust correlation-driven non-Fermi liquid characteristic under any electron density. Introducing hole carriers to the half-filled FK leads to Mott insulator-metal transition, where the Mott quantum criticality manifests unconventional scaling behavior in transport properties. Further insight on the violation of the Luttinger's theorem is examined by combining Hubbard-I approximation with a composite fermion picture, which emphasizes the importance of a mixed excitation of the itinerant electron and the composite fermion. Interestingly, when compared FK model with a binary disorder system, it suggests that the two-peak band structure discovered by Monte Carlo and Hubbard-I approaches is underlying the violation of Luttinger's theorem.Comment: 10 pages, 9 figure

Compensation effect in carbon nanotube quantum dots coupled to polarized electrodes in the presence of spin-orbit coupling

We study theoretically the Kondo effect in carbon nanotube quantum dot attached to polarized electrodes. Since both spin and orbit degrees of freedom are involved in such a system, the electrode polarization contains the spin- and orbit-polarizations as well as the Kramers polarization in the presence of the spin-orbit coupling. In this paper we focus on the compensation effect of the effective fields induced by different polarizations by applying magnetic field. The main results are i) while the effective fields induced by the spin- and orbit-polarizations remove the degeneracy in the Kondo effect, the effective field induced by the Kramers polarization enhances the degeneracy through suppressing the spin-orbit coupling; ii) while the effective field induced by the spin-polarization can not be compensated by applying magnetic field, the effective field induced by the orbit-polarization can be compensated; and iii) the presence of the spin-orbit coupling does not change the compensation behavior observed in the case without the spin-orbit coupling. These results are observable in an ultraclean carbon-nanotube quantum dot attached to ferromagnetic contacts under a parallel applied magnetic field along the tube axis and it would deepen our understanding on the Kondo physics of the carbon nanotube quantum dot.Comment: 8 pages, 6 figure

catena-Poly[[dichloridocopper(II)]-μ-4,4′-bis­(benzimidazol-1-yl)biphen­yl]

In the title compound, [CuCl2(C26H18N4)]n, the Cu(II) ion is four-coordinated by two N atoms from two 4,4′-bis­(benzo­imidazol-1-yl)biphenyl ligands and two chloride anions, in a slightly distorted tetra­hedral environment. The biphenyl ligand acts as a linear bidentate ligand, connecting the metal atoms into an infinite chain parallel to [101]. In the biphenyl ligand, the two benzene rings make a dihedral angle of 33.19 (7)°

Modulation of the thermodynamic, kinetic and magnetic properties of the hydrogen monomer on graphene by charge doping

The thermodynamic, kinetic and magnetic properties of the hydrogen monomer on doped graphene layers were studied by ab initio simulations. Electron doping was found to heighten the diffusion potential barrier, while hole doping lowers it. However, both kinds of dopings heighten the desorption potential barrier. The underlying mechanism was revealed by investigating the effect of doping on the bond strength of graphene and on the electron transfer and the coulomb interaction between the hydrogen monomer and graphene. The kinetic properties of H and D monomers on doped graphene layers during both the annealing process (annealing time $t_0 =$300 s) and the constant-rate heating process (heating rate $\alpha =$1.0 K/s) were simulated. Both electron and hole dopings were found to generally increase the desorption temperatures of hydrogen monomers. Electron doping was found to prevent the diffusion of hydrogen monomers, while the hole doping enhances their diffusion. Macroscopic diffusion of hydrogen monomers on graphene can be achieved when the doping-hole density reaches $5.0\times10^{13}$ cm$^{-2}$. The magnetic moment and exchange splitting were found to be reduced by both electron and hole dopings, which was explained by a simple exchange model. The study in this report can further enhance the understanding of the interaction between hydrogen and graphene and is expected to be helpful in the design of hydrogenated-graphene-based devices.Comment: Submitte

Colorless and Transparent high – Temperature-Resistant Polymer Optical Films – Current Status and Potential Applications in Optoelectronic Fabrications

Recent research and development of colorless and transparent high-temperature-resistant polymer optical films (CHTPFs) have been reviewed. CHTPF films possess the merits of both common polymer optical film and aromatic high-temperature-resistant polymer films and thus have been widely investigated as components for microelectronic and optoelectronic fabrications. The current paper reviews the latest research and development for CHTPF films, including their synthesis chemistry, manufacturing process, and engineering applications. Especially, this review focuses on the applications of CHTPF films as flexible substrates for optoelectrical devices, such as flexible active matrix organic light-emitting display devices (AMOLEDs), flexible printing circuit boards (FPCBs), and flexible solar cells

Kondo effect of an adatom in graphene and its scanning tunneling spectroscopy

We study the Kondo effect of a single magnetic adatom on the surface of graphene. It was shown that the unique linear dispersion relation near the Dirac points in graphene makes it more easy to form the local magnetic moment, which simply means that the Kondo resonance can be observed in a more wider parameter region than in the metallic host. The result indicates that the Kondo resonance indeed can form ranged from the Kondo regime, to the mixed valence, even to the empty orbital regime. While the Kondo resonance displays as a sharp peak in the first regime, it has a peak-dip structure and/or an anti-resonance in the remaining two regimes, which result from the Fano resonance due to the significant background leaded by dramatically broadening of the impurity level in graphene. We also study the scanning tunneling microscopy (STM) spectra of the adatom and they show obvious particle-hole asymmetry when the chemical potential is tuned by the gate voltages applied to the graphene. Finally, we explore the influence of the direct tunneling channel between the STM tip and the graphene on the Kondo resonance and find that the lineshape of the Kondo resonance is unaffected, which can be attributed to unusual large asymmetry factor in graphene. Our study indicates that the graphene is an ideal platform to study systematically the Kondo physics and these results are useful to further stimulate the relevant experimental studies on the system.Comment: 8 pages, 5 figure