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971.
Instrumental characterization of clay by XRF,XRD and FTIR 总被引:2,自引:0,他引:2
Instrumental characterizations of the clay were performed by different techniques such as XRF, XRD and FTIR. XRF shows the
chemical compositions of the clay where Al-oxide and silica oxide are present in major quantity whereas XRD confirms the presence
of these minerals in clay. FTIR studies show the presence of quartz, alumina, haematite and different mineral matters. 相似文献
972.
Thin layers of silver and titanium were deposited onto commercial Ti–48Al particles by magnetron sputtering prior to their consolidation by hot isostatic pressing and subsequent heat treatment.
Based on picnometry and electron probe microanalysis results, average values of 1.5 and 2.5 at.%, respectively, were obtained
for the silver and titanium contents in the coated particles. The surface modified Ti–48Al particles exhibited improved sintering ability than the unmodified ones. The consolidated samples have duplex microstructures
formed by γ-TiAl and γ-TiAl + α2-Ti3Al grains. Ag-rich nanoprecipitates were detected in the microstructure of the compacted Ti-48Al + Ag sample. The coatings are no longer visible at the grains boundaries after a subsequent homogenization heat treatment
at 1200°C. The highest values of hardness and Young’s modulus were obtained for the Ti–48Al + Ag sample, associated with a higher density and a lower percentage of pores. 相似文献
973.
Moshe Dayan 《Journal of Superconductivity and Novel Magnetism》2007,20(3):239-247
Here I establish the field perturbation theory of pseudogaps in HTSC. The proposed ground state suggests an internal particle-hole
field, which is normal to nesting surfaces, and having twice the Fermi wave number. It is proved that the system violates
momentum conservation by the wave vector of this internal field. This violation applies to the quasi-particle propagators,
as well as to the interactions. Interaction vertices via the Pauli matrix-τ1 are established. This, in turn, establishes the validity of the pseudogap Hartree self-energy. 相似文献
974.
The reaction between MgO and graphite powders under flowing argon atmosphere was studied using a dynamic thermogravimetric
method. In the temperature range 293 to 1973 K, the effects of compacting pressure, magnesia/carbon ratio, heating rate, Ar
carrier-gas flow rate, and CO-partial pressure were investigated. An experimentally determined reaction mechanism was proposed
and discussed. The reduction process could be divided into two stages. The first stage includes the direct reaction between
MgO and graphite particles and partial gas-solid reaction at relatively low temperature (below 1750 K). The overall reaction
rate depends on the solid phase-boundary reaction between magnesia and carbon particles. The second stage is the gas-solid
reaction between CO and MgO, which determines the overall reaction rate. The apparent activation energies of the two stages
were estimated to be 208.29 and 374.13 kJ/mol, respectively. 相似文献
975.
The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02 data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing. 相似文献
976.
977.
978.
Jan Paca Eva Klapkova Martin Halecky Kim Jones Carlos Riccardo Soccol 《Clean Technologies and Environmental Policy》2007,9(1):69-74
The removal of a mixture of painting solvents from waste air using a biofiltration process was evaluated in this project.
The pollutants removed included hydrophobic (aromatic hydrocarbons) and hydrophilic (water soluble ketones and esters) compounds.
A trickle bed reactor with a defined immobilized mixed culture on polyethylene Pall rings was utilized in this biodegradation
study. The removal efficiencies (RE) of the individual groups of pollutants during loading experiments were determined. An
increase of the aromatic hydrocarbons loading resulted in a drop of their REAROM with no effect on the RE value of ketones. The overloading of ketones caused a rapid drop in REAROM and a small drop in REKET. To achieve a restoration of the biocatalyst degradation properties after the increase in loading, an addition of phosphate
to the aqueous medium was implemented which successfully restored the removal efficiency. 相似文献
979.
980.
Dynamic neural networks with different time-scales include the aspects of fast and slow phenomenons. Some applications require
that the equilibrium points of the designed networks are stable. In this paper, the passivity-based approach is used to derive
stability conditions for dynamic neural networks with different time-scales. Several stability properties, such as passivity,
asymptotic stability, input-to-state stability and bounded input bounded output stability, are guaranteed in certain senses.
A numerical example is also given to demonstrate the effectiveness of the theoretical results. 相似文献