Investigation of the structure of the surface of sorbents–catalysts modified with MnO<Subscript>2</Subscript> by the method of X-ray photoelectronic spectroscopy

crystal films of manganese oxide of composite materials were investigated by the method of X-ray photoelectronic spectroscopy in the fresh and spent state. The efficiency of modification was confirmed whereby on the surface of substrates of the carbonate type forms a thin-film crystalline structure of MnO₂. We have found the relationship between the structure of crystalline film and substrate nature, which affects technical characteristics of the sorbent–catalyst. The mechanism of catalytic oxidation of manganese compounds in aqueous solutions using synthesized sorbents–catalysts was defined.     

Information-theoretic analysis of efficiency of the phonetic encoding–decoding method in automatic speech recognition

A words phonetic decoding method in automatic speech recognition is considered. The properties of Kullback–Leibler divergence are used to synthesize the estimation of the distribution of divergence between minimum speech units (e.g., single phonemes) inside a single class. It is demonstrated that the minimum variance of the intraphonemic divergence is reached when the phonetic database is tuned to the voice of a single speaker. The estimations are proven by experimental results on the recognition of vowel sounds and isolated words of Russian language.     

Formation of High-Coercivity State in Fe2NiAl Alloy During Decomposition of Solid Solution Under Quenching from Liquid State and Subsequent Annealing

Metal Science and Heat Treatment - The methods of transmission electron microscopy, atomic force microscopy, x-ray diffraction, and magnetic measurements were used to study the laws of formation of...     

Structure and magnetic properties of the Nd<Subscript>9.5</Subscript>Fe<Subscript>84.5</Subscript>B<Subscript>6</Subscript> alloy subjected to severe plastic deformation and annealing

The effect of severe plastic deformation (SPD) by torsion and subsequent annealing on the structure and magnetic properties of the cast Nd_9.5Fe_84.5B₆ alloy is studied. SPD by torsion is shown to lead to partial amorphization of the Nd₂Fe¹⁴B phase and the precipitation of α-Fe; subsequent annealing results in the crystallization of the amorphous phase and the formation of a nanocomposite Nd₂Fe₁₄B/α-Fe structure. After SPD by torsion at 20 revolutions and annealing at 873 K, the (101) texture is formed; in this case, the coercive force is H _c = 360 kA/m and the maximum energy product is (BH) _max = 166 kJ/m3. The residual magnetization and the squareness ratio of the hysteretic loop of the textured alloy decrease as the ambient temperature decreases.     

Structures formed during the friction of a metal-ceramic composite on steel under high-velocity sliding conditions

We present the results of investigations of the structures of friction surfaces and tribological characteristics of a ceramic-metal (WC-steel 110G13) composite upon dry friction on steel in a rod-on-disk configuration in a range of sliding velocities from 0.65 to 40 m/s at a pressure of 2 MPa. The region of catastrophic wear in this system is observed at 23–30 m/s and is followed by a region of steady-state wear at a sliding velocity above 30 m/s. The sharp increase in the rate of wear at 23–30 m/s is related to a change in the wear mechanism. It is established that three layers with different structures and properties are formed in the WC-steel 110G13 composite near the friction surface.     

A Method for Measuring the Pitch Frequency of Speech Signals for the Systems of Acoustic Speech Analysis

Measurement Techniques - We developed a new method for measuring the pitch frequency of speech signals with elevated noise immunity. The problem of protection against intense background noise is...     

Normative Conspiracy Theory

Automation and Remote Control - The author introduces a new model based on a correlated extension of normal-form games to describe the players’ behavior in environments that allow information...