Influence of Titanium Excess in a Ti–Si Reaction Mixture on the Synthesis of a Composite in a Combustion Wave

Theoretical Foundations of Chemical Engineering - On the basis of the classic concepts of the theory of solid-phase combustion, for the first time, a model with a detailed scheme of chemical...     

Gold nanorods with a hematoporphyrin-loaded silica shell for dual-modality photodynamic and photothermal treatment of tumors in vivo

Nanocomposites （NCs） consisting of a gold nanorod core and a mesoporous silica shell doped with hematoporphyrin （HP） have been fabricated in order to improve the efficiency of cancer treatment by combining photothermal and photodynamic therapies （PDT ＋ PTT） in vivo. In addition to the long-wavelength plasmon resonance near 810-830 nm, the fabricated NCs exhibited a 400-nm absorbance peak corresponding to bound HP, generated singlet oxygen under 633-nm excitation near the 632.5-nm Q-band, and produced heat under a 808-nm near-infrared （NIR） laser irradiation. These modalities were used for a combined PDT ＋ PTT treatment of large （about 3 cm3） solid tumors in vivo with a xenorafted tumor rat model. NCs were directly injected into tumors and irradiated simultaneously with 633-nm and 808-nm lasers to stimulate the combined photodynamic and photothermal activities of NCs. The efficiency of the combined therapy was evaluated by optical coherence tomography, histological analysis, and by measurements of the tumor volume growth during a 21-day period. The NC-mediated PDT led to weak changes in tissue histology and to a moderate 20% decrease in the tumor volume. In contrast, the combined PDT ＋ PTT treatment resulted in the large-area tumor necrosis and led to dramatic decrease in the tumor volume.     

A set of test and measuring equipment in the field of electromagnetic compatibility

Instrumental support of scientific research and EMC tests are considered. Sample generators of field and conducted interferences of microsecond, nanosecond, and subnanosecond ranges are given. The structure of an optoelectronic electromagnetic field gage is described. Characteristics of TEM and GTEM chambers are given.     

Interaction of a System of Initially Unexcited Two-level Atoms with a Weak Cavity Field

Abstract

Using a perturbation method, constructed in terms of SU(2) group representations, the interaction of N initially unexcited two-level atoms and a weak single-mode cavity field is studied. The field is assumed to be initially either in a Fock state with a number of photons equal to n or in a coherent state. In the case of the photon-number state with n  3, the pure phenomenon of collective collapses and revivals manifests itself. For the initially coherent field the phenomenon of collapses and revivals arising from the photon number distribution mechanism is additionally modulated by this collective mechanism. The problem of the interaction of excited atoms with an initially coherent field has already been solved numerically by Barnett and Knight. For n=1 2 and 3 the approximate solution is compared with the exact solutions also given in this paper and the limit of applicability of our approach is established.     

Heat and mass transfer in the heterogeneous system matrix-inclusions under pulse electron-beam processing

A mathematical model of pulse electron-beam processing of a heterogeneous material with allowance for the fact that each phase (particles and the matrix) possess its own properties and thus is characterized by its own concentration and temperature has been proposed. The processes of transfer of heat and mass in particles and the matrix and exchange processes between the phases have been taken into account. An example of a partial problem enabling one to calculate the coefficients of heat and mass exchange between the phases as functions of the temperature and the particle size has been given. The influence of the character of the external heat flux on the temperature and concentration fields in particles and the matrix has been illustrated. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 81, No. 1, pp. 147–156, January–February, 2008.     

Experience in sinking bored,underreamed piles in the Ukraine

Soil Mechanics and Foundation Engineering -     

Prediction of Local and Global Ionization Effects on ICs: The Synergy between Numerical and Physical Simulation

A review is presented of an integrated approach to hardness assurance, embracing single-event and global pulsed-ionization effects. The strategy essentially combines numerical and physical simulation in order to obtain reliable data on IC radiation response with minimum expenditure of time and money. The way in which calculations and measurements should be combined depends on the type of IC and the radiation conditions. It is shown that the cost of measurement can be reduced by using laboratory radiation simulators and each form of radiation of interest can be simulated with an agent readily available for the tester. Particular coverage is given to simulation with lasers.     

One-Parameter Model for the Estimation of IC Susceptibility to Proton-Induced Single-Event Upsets

Singe-event upsets (SEUs) caused by high-energy protons are considered. An analytical model is proposed to represent the dependence of SEU cross section on proton energy. The model is based on a simple mechanism of proton-induced nuclear reactions in silicon. A computer simulation is conducted by the model. The results are found to agree with previous experiments. They indicate that the model enables one to predict susceptibility to proton-induced SEUs on the basis of a single value of SEU cross section measured at a proton energy higher than 100 MeV. It is shown that the approach may also work for heavy ions.