Improved performance of organic light-emitting diodes with dual electron transporting layers

In this study the performance of organic light-emitting diodes （OLEDs） are enhanced significantly, which is based on dual electron transporting layers （13phen/CuPc）. By adjusting the thicknesses of Bphen and CuPc, the maximal luminescence, the maximal current efficiency, and the maximal power efficiency of the device reach 17570 cd/m^2 at 11 V, and 5.39 cd/A and 3.39 lm/W at 3.37 mA/cm^2 respectively, which are enhanced approximately by 33.4%, 39.3%, and 68.9%, respectively, compared with those of the device using Bphen only for an electron transporting layer. These results may provide some valuable references for improving the electron injection and the transportation of OLED.

Features of the Process of Self-Propagating High-Temperature Synthesis, a Structure and Strong Properties of Borides Iron Layers on the Carbon Steels, Generated Under a Powerful Electron Beam in Vacuum

Conditions of formation, structure and properties of boride iron layers on carbonaceous steels 3 and 45 at electron beam borating are investigated. New process to make layers of iron borides （Fe2B, FeB） using electron beam are reported. The microstructure and microhardness of boride layers are investigated and also are compared to layer properties obtained at solid phase borating. Formed layers were heterogeneous structure combining solid and weak components and resulting in to fragility reduction of boride layer.

To the Question of the Independence of the Surface Electromagnetic Wave Frequency

Earth's the surface is often strongly inductive,consisting of a dielectric layer thickness endpoint lying on an unlimited conductor basis.Electro-magnetic wave,spreading along the surface,it appears captured dielectric layer,spreading it as in the waveguide channel.Waveguide theory it is known that the spread in the waveguide can only electromagnetic waves with a discrete set of frequencies.And experience shows that the captured waveguide channel electromagnetic waves can be any frequency.The article found that this behavior is due to the fact that electromagnetic waves in free space border-dielectric layer damped height in several wavelengths.Thus the thickness of the dielectric layer becomes more effectively,and this leads to a reduction of the minimum frequency of the waveguide.A discrete set of frequencies is blurred so that cover each other.Thus,a discrete set of frequencies becomes solid,and captured waveguide channel electromagnetic waves are independent of frequency.

Fractal Geometry:Axioms,Fractal Derivative and Its Geometrical Meaning

Physics success is largely determined by using mathematics.Physics often themselves create the necessary mathematical apparatus.This article shows how you can construct a fractal calculus-mathematics of fractal geometry.In modem scientific literature often write from a firm that"there is no strict definition of fractals",to the more moderate that"objects in a certain sense,fractal and similar."We show that fractal geometry is a strict mathematical theory,defined by their axioms.This methodology allows the geometry of axiomatised naturally define fractal integrals and differentials.Consistent application on your input below the axiom gives the opportunity to develop effective methods of measurement of fractal dimension,geometri-cal interpretation of fractal derivative gain and open dual symmetry.

Impedance,What It Is,How It Is Measured,and Why It Is Needed

Impedance is the basic concept and quantity when measuring an electromagnetic field near the earth’s surface.It is shown how the antennas of the IPI device are oriented,and how the coordinate system is set.It is established why the phase difference of the electromagnetic field component is limited to the limits from zero to minus ninety degrees.The introduction of the basic electrophysical characteristics of a continuous medium-dielectric constant and electrical conductivity-is considered.For a homogeneous medium,the dependence of impedance on electrophysical quantities is given.The Riccati equation for impedance is given.Not only the horizontal arrangement of the electrical cable is considered,but also the vertical one.The latter allows you to explore the electrical parameters of the media.

Rings Structures on Ice Lake Baikal

On cosmic picture of the ice surface lake Baikal are discovered dark ring by diameter 7 km-8 km.The author shall give physical interpretation given phenomenon,having expected that shaping rings are connected with surge of the warm natural gas from sedimentary thick mass of the bottom of the Baikal.Convection is formed in thick mass of water in the manner of torah around surge of the natural gas,which carries become warm water before surface(the lower edge ice)in side from pole of the natural gas.The mechanism heatconductivity heat gets to upper edge ice,where snow and ice begin intensive to melt.As a result thawed patch is formed on snow-clad ice in the manner of ring.