Mechanical performance of nano-silica modified insulating paper with mechanical-thermal synergy

In this paper, the mechanical properties of nano-silica modified insulating paper under the combined action of mechanical vibration and temperature conditions are studied. Unmodified and nano-silica modified cellulose insulating paper with 2 wt% and 4 wt% were prepared, respectively, and a series of mechanical-thermal synergy experiments were carried out. With the same mechanical stress and temperature, and with the same aging duration of 144 h (6d), the tensile strength of modified insulating paper with 4 wt% nano-silica, increased 9.9 N and 5.5 N, respectively, compared with those of the unmodified and the 2 wt% nano-silica modified insulating paper. The experiments indicate that the nano-silica modification can effectively improve the mechanical properties of insulating paper. In this work, the modified mechanism of nano-silica is analyzed from the interface effect of modified polymer and the quantum effect of the modified polymer interface two aspects. It is shown that the interface formed in the modified insulating paper can transfer the mechanical stress acted on the insulating paper and prevent the cracks formed in the aging process of the test sample from further expansion, while the quantum effect discretizes the electron energy level, which can restrict the motion of the molecular chain segment to some extent. The conclusion can be used for reference to improve the performance of insulating paper.

Effect of Reactive Self-Assembled Monolayer at the Anode Interface of Organic Light-Emitting Diode

Organic light-emitting diodes (OLEDs) were prepared on indium-tin oxide (ITO) substrates that were modified with various self-assembled monolayers (SAMs) including those which have reactive terminal units. The OLED performance was analyzed in terms of molecular length, dipole moment and HOMO level of SAM molecules estimated by the density functional theory calculation. It was suggested that the current efficiency of OLED is partly improved by controlling the carrier balance, interfacial dipole moment, and electron energy level by SAM modification. More importantly, remarkable improvement in OLED efficiency was achieved by chemically tethering the inorganic/organic interface via benzophenone-terminated SAM. The reactive SAM having benzophenone terminal group can be a promising tool to control the inorganic/organic interface for organic devices.

Quantum Electrostatic Model for Optical Properties of Nanoscale Gold Films

The optical properties of thin gold films with thickness varying from 2.5 nm to 30 nm are investigated. Due to the quantum size effect, the optical constants of the thin gold film deviate from the Drude model for bulk material as film thickness decreases, especially around 2.5 nm, where the electron energy level becomes discrete. A theory based on the self-consistent solution of the Schrödinger equation and the Poisson equation is proposed and its predictions agree well with experimental results.

Electron energy level engineering in Zn1−xCdxSe nanocrystals

Variation in composition provides an additional degree of freedom in nanocrystals design.

A MATHEMATICAL THEORY FOR VIBRATIONAL LEVELS ASSOCIATED WITH HYDROGEN BONDS II: THE NON-SYMMETRIC CASE

We propose an alternative to the usual time-independent Born–Oppenheimer approximation that is specifically designed to describe molecules with non-symmetrical hydrogen bonds. In our approach, the masses of the hydrogen nuclei are scaled differently from those of the heavier nuclei, and we employ a specialized form for the electron energy level surface. As a result, the different vibrational modes appear at different orders of approximation. Although we develop a general theory, our analysis is motivated by an examination of the FHCl- ion. We describe our results for it in detail. We prove the existence of quasimodes and quasienergies for the nuclear vibrational and rotational motion to arbitrary order in the Born–Oppenheimer parameter ∊. When the electronic motion is also included, we provide simple formulas for the quasienergies up to order ∊3 that compare well with experiment and numerical results.

QUANTUM SIZE EFFECTS OF HYDROGEN IMPURITY AT OFF-CENTER DONOR ATOM IN SPHERICAL QUANTUM DOTS

We obtain the numerical solutions for a single electron energy level of a hydrogen impurity confined inside an off-center donor in a spherical quantum dot. The energy spectrum of single electron impurity for off-center donor atom subject to screened Coulomb's attractive potential barrier well is presented. Using B-spline finite element method, we generate a complete set of wavefunctions within the central unit cell, and through the perturbation theory, the whole energy spectrum of an impurity at low temperature can be explored. We find that the energy splitting and different related magnetic quantum number ml, i.e., (n, l, ml) varies with quantum dot size. This is due to the fact that quantum confinement effect lifts the degeneracy which comes from the Coulomb interaction. On the other hand, the phenomena of energy spectrum splitting under this model is an analogous case, considering that degeneracy of hydrogen energy levels in free space has been lifted by an external magnetic field (Zeeman effect).

The Effects of Substrate Temperature on Optical Properties and Surface Morphology of Nickel Phthalocyanine Thin Films Grown by Organic Evaporator System

Thin films of Nickel Phthalocyanine (NiPc) are prepared at a base pressure of 10-6 mbar using Organic Evaporator System. The films are deposited onto the glass substrate at various temperatures of 100 0C, 120 0C, 140 0C and 160 0C. Crystalline of NiPc thin films was investigated by X-ray diffraction (XRD) spectroscopy. XRD patterns exhibit to become aggravated crystalline films as monoclinic structure. Surface morphology of NiPc thin films was characterized by field emission scanning electron microscope (FE-SEM). FE-SEM micrographs indicate that fiber-like morphology of NiPc is enhanced with increasing substrate temperature. The optical absorption spectra of these thin films are measured. Present studies reveal that the Q-band of NiPc thin films appears as the change of electron energy level. Absorption spectra obtained from UV-vis of deposited NiPc are declined as the substrate temperature is risen.