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We study theoretically the spin polarized electron field emission from carbon nanotube (CN) within an axial magnetic field. It is found that the spin polarization of emission current can reach 0.05~0.08 with 0.1~1 μA emission current in the magnetic field 6 T and the electric field 9~12 V/nm at room temperature. The spin polarizations of the energy distributions oscillate and the peaks reach to 0...
The relation between electrical breakdown and mechanical properties in soft polymeric materials is of particular interest for multiple applications, such as smart and flexible materials. In the literature, this relation is commonly investigated by variation of temperature, which indirectly causes a change in mechanical properties, but it also affects other factors that may influence the electrical...
Structural and luminescent properties of UV emitting ZnAl2O4 powder was studied. It was found that the firing temperature above 1000οC was necessary to prepare the ZnAl2O4 single phase. The CL intensity became stronger according to increase of firing temperature, because of improvement of crystallinity of the powders. The peak position of CL spectra were shifted from 235 nm to 250 nm by control of...
FeNi3 nanospheres (NS) with an average diameter of 400 nm were synthesized by a simple low temperature reduction method. FeNi3@C core-shell structured nanocapsules (NC) were then fabricated with a hydrothermal process. The electromagnetic (EM) properties of paraffin matrix composites containing FeNi3 NS and FeNi3@C NC were studied at 2-18 GHz. The effect of dielectric carbon coating on the EM properties...
Distribution of electric field across the insulation of high voltage direct current (HVDC) is affected by the conductivity of the material, which is a function of both temperature and electric field. To understand the effect of temperature on the conductivity of the insulation across a dc power cable under load condition, an investigation is conducted on the electrical conductivity of the cross-linked...
This paper present calculations showing the interest of to make gyroscopes that use cuts normal to a three fold symmetry axis of several new materials of call 32 or 3m to build sensitive and stable gyroscopes using lateral field excitation and detection. The main factors of the sensitivity are studied and it is shown that lithium tantalate and gallium phosphate present an interesting ensemble of very...
In order to resolve the problem of deficiency in the data of slab thermal properties during calculating the slab temperature in heating furnace, a new method using artificial neural networks to estimate the slab thermal properties is introduced. Based on the fact of the thermal properties change mainly with the chemical ingredients and the temperature, two BP neural networks which work together and...
Temperature is considered to be one of the most important aspects to take into account in dry hard machining. However, dry hard machining is a complex process, and the temperature is the most difficult to be measured when machining. Up to now, only very few studies have been reported on influence of tool wear and depth of cut on temperature fields produced during dry hard machining AISI D2 steel in...
The thermal degradation and light capture performance of CuInGaSe2 (CIGS) and c-Si photovoltaic devices were explored. Typically thin-film polycrystalline materials such as CIGS are hypothesized to be advantaged over single crystal Si solar cells as having lower thermal performance and improved light capture response. To this end, we present our evaluation of the thermal and light capture performance...
The adsorption of diesel oil in seawater on biodegradable adsorbing material and the influencing factors such as salinity, pH and temperature were studied. Results showed the adsorption of diesel fitted the second-order reaction model, and the saturated adsorption capability was 6.69g/g which can be reached in 10-20min. The diesel oil removal efficiency increased with the increment of salinity and...
Volatile organic compounds (VOCs) emitted from larch particleboard at different temperatures were studied in this paper. The small climate chamber and portable VOC gas monitor were used to measure VOCs quantities. Particleboard 1 (with hot-pressing time 3.5 min and hot-pressing pressure 35 MPa) and particleboard 2 (with hot-pressing time 2.7 min and hot-pressing pressure 30 MPa) were respectively...
In order to make use of jujube residue, insoluble dietary fiber from jujube residue was prepared by using auxiliary alkal method . The functional characteristics of insoluble dietary were also studied, such as water holding capacity, expansibility and fat adsorption capacity. The optimum parameters obtained by orthogonal experiment were as follows : NaOH concentration 0.4mol/L , soaking temperature...
Biomass energy is an important resource in resolving the energy crisis and pyrolysis is the most important method in making use of it. Pyrolysis in the absence of oxygen is called as carbonization. Biomass could be converted to charcoal, liquid and gas products using the carbonization process at different temperatures. The chemical composition and yields of charcoal, liquid and gas are determined...
The rapid assembly of printed circuit boards to meet the desired goal of thinning the board creates more complexity in the reflow process, to control the occurrence of warpage in the board. Therefore, certain methods are preferred for simply yet accurately predicting the amount of warpage inevitable in the reflow process. Responding to such a need, the study was carried out aiming to provide a specific...
DI materials were quenched at the temperature of 250°C, 300°C, 350°C and with the isothermal time of 1h, 2h and 3h respectively. So there were nine different ADI materials, which owned different mechanical properties. Through analyzing the changes of their metallographic structures, curves of the relationships between quenching temperatures, isothermal time and materials intensity, hardness could...
In the process of seamless pipe production, residual stress produced in the straightening process affects the mechanical performance of seamless pipe. Therefore, systematic investigation has been carried out in this paper to find out how residual stress distribution is related to the straightening reduction and temperature in order to meet the tolerance requirements. In the meantime, a detailed analysis...
Tobermorite is a mineral material with good ion exchange properties. The potassium feldspar ore from Lushi country is muscovite syenite. Potassium feldspar was hydrothermally decomposed with CaO as an additive, and then tobermorite nano-scale powder was synthesized. Based on the research work of our group, the adsorption property of tobermorite to Pb2+ from aqueous solution was studied. The factors...
According to the existing theories of soil mechanics and fluid mechanics, as well as the features about the water and soil curves of unsaturated expansive soil. It is obtained the equations about gaseous water transfer and liquid water transfer of unsaturated expansive soil. It is be seen from coefficients in the equation that water migration bringing water content changes relating to moisture gradient,...
Among the various Pb-free solder alloys, Sn-3.0Ag-0.5Cu has been an industrial standard in consumer electronics due to its moderate wetting behavior and reliability in thermal fatigue. Recently, however, its high material cost and low reliability in drop impact condition resulted in the use of Sn-0.3Ag-0.7Cu and the development of Sn-1.2Ag-0.7Cu-0.4In solder alloys. Authors have reported that the...
Indoor formaldehyde(HCHO) pollution is harmful to human health. The purpose of this study was to investigate the indoor HCHO situation in residential apartments in Beijing and observe the character of the concentrations. According to Indoor air quality standard (GB/T 18883-2002), HCHO concentrations in decorated apartments were investigated during 2005-2007. All data were to be statistical with SPSS...
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