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Ni(Al, C) mixed (substitutional and interstitial) solid solutions have been synthesized by mechanical alloying; the atomic ratio of Ni and Al was constant at 3: 1, but the concentration of carbon was varied. A carbide-forming element CE (Ti, Nb, or Hf) was added to the formed solid solutions with nanocrystalline substructures; the size D of coherent scattering regions was 4–6 nm. These mixtures Ni(Al, C) + CE were subjected to mechanical activation (short-term milling) and subsequent hot isostatic pressing. According to X-ray phase analysis, compacted samples exhibited three phases: Ni3AlCx antiperovskit, Ni(Al) solid solution with D = 50–100 nm and corresponding metal monocarbides (TiC, NbC, or HfC; D ≈ 7 nm) located at boundaries. These results were confirmed by scanning electron and optical microscopy. Thus, we obtained the analog of the conventional high-temperature γ/γ′ alloys hardened by grain-boundary nanoscale carbides, which prevent recrystallization.

The LIU-2 induction accelerator is described. It is used as an injector for the developed large linear induction accelerator with a maximum electron beam energy of 20 MeV, which is intended for smallangle pulse X-ray tomography. Owing to the good quality and high current of the electron beam (2 kA), the injector is capable of operating as an independent X-ray source with an electron energy of 2 MeV, the beam diameter at the target of 1 MeV is ∼20% of the total energy yield. The spread of the radiation intensity in the solid angle of 10° is ±5%, and the absorbed dose at a distance of 1 m from the target is 32 × 10−3 Gy, which allows this source to be used with attenuation of 103–104 for exposure of available X-ray films. This type of system is characterized by a high transmission capability with a 0.5-mm maximum spatial resolution of X-ray images and can be used in the X-ray imaging technique when carrying out gas-dynamic testing of products with an optical thickness as great as 90 mm of lead equivalent.

Nanocrystalline mixed (substitutional/interstitial) solid solutions have been prepared by milling four-component mixtures with the overall compositions (Ni2.8AlCr0.2)C0.5 and (Ni3Al0.8Cr0.2)C0.5. Analysis of X-ray diffraction data indicates that the formation of the solid solutions is accompanied by an increase in deformation stacking fault probability, which is directly related to the amount of dissolved carbon. Our results demonstrate that the heating-induced ordering of the solid solutions occurs in several steps. Nucleation of the antiperovskite phase E21 occurs through spinodal decomposition of the Ni(Al,Cr,C) solid solution starting at 400°C. Heating to higher temperatures leads to partial Cr precipitation from the ordered phase and the formation of the chromium carbide Cr3C2, which reduces the carbon content of the antiperovskite phase.

The method for the mechanical alloying of Ni-Al-C and Ni3Al-C mixtures was used to obtain nonequilibrium solid Ni(Al,C) solutions in which the carbon content varies from 2.9 to 8.5 at %. The relationship between carbon dissolution and the probability of appearance of deformation-induced stacking faults (SFs) in the formation of mixed (substitutional and interstitial) solid Ni(Al,C) solutions has been found based on an analysis of the diffraction spectra. SFs are assumed to serve as pathways of carbon penetration in nickel-based solid solutions. The effective carbon radius was found to be about 0.0616 nm in the formation of an antiperovskite phase Ni3AlC x . The method of calculating the amount of interstitial carbon was proposed based on the experimental lattice parameters of fcc solid Ni(Al,C) solutions and ordered phases L12 Ni3Al and E21 (Ni3AlC x ). The temperature stability of the nonequilibrium solid Ni(Al,C) solutions was established. It was shown that the decomposition of the solid solutions proceeded according to a spinodal mechanism at a temperature of 400°C with separation into two phases, i.e., an antiperovskite carbide (Ni3AlC x ) and Ni(Al,C). At higher temperatures (600–800°C), carbon precipitates from these phases with the formation of an antiperovskite Ni3AlC0.16, solid Ni(Al) solution, and nanocrystalline graphite.

Mechanochemical processing of elemental mixtures with the compositions Ni75Al25, Ni70Al25Cr5, and Ni75Al20Cr5 (5 at % Cr in the mixtures instead of the equivalent amount of Ni or Al) leads to the formation of nanocrystalline nickel-based solid solutions (crystallite size in the range ≃ 7–12 nm). Comparison of experimentally determined lattice parameters of the solid solutions with Vegard’s law values and with the lattice parameters evaluated using the Bozzolo-Ferrante rule, which takes into account the bulk moduli of constituent elements, suggests that the atoms in the solid solutions are bonded more strongly. Heating the synthesized ternary solid solutions in a calorimeter to 1000°C leads to the formation of an ordered γ′-phase (L12). Analysis of the relative intensity ratio of superlattice and fundamental reflections indicates that the Cr atoms always reside in the Al sublattice, independent of the composition of the starting mixture. When 5 at % Cr is incorporated instead of Ni, the chromium atoms force out aluminum from the Al sublattice, and the Ni deficiency in the Ni sublattice is compensated by the Al atoms. The ordered phases remain nanocrystalline (crystallite size in the range ≃ 40–70 nm).

A pulse power system of the induction electron accelerator intended for parameters of 2 MeV, 2 kA, and operating in the double-pulse mode is presented. The schematic diagram and main elements of the pulse system are described, and the main technical solutions intended to produce a set of pulses with 21-kV peak voltages, peak currents of up to 8 kA, and 200-ns durations across a resistive-inductive load are indicated. The experimental data, which were obtained when separate units and the whole power system operated on the rated duty, are given.

The structure, operation logic, and hardware tools of the control system of a linear induction accelerator for an X-ray complex are considered. The hardware developed in the CompactPCI standard for the control system is described. The possibility of embedding of smart microelectronic equipment into high-voltage elements of the facility is analyzed.

Colour characteristic temperature dependence of such as X- and Y-coordinates (CIE 1931) for high power blue laser diode was investigated. It was shown, that thermal stability of colour characteristic of high power blue laser diode allows to create solid state lighting.

A double pulse modulator is described that is capable of generating two pulses of 200 ns duration at peak currents up to 10 kA with the delay between pulses as short as 2 μs. The TPI1-10k/50 tetrode and the TPI5-10k/50 pentode cold cathode thyratrons, which can be operated at voltages up to 50 kV, have been used as switching elements. A voltage hold-off recovery time of less than 1 μs has been demonstrated at an operating current of 7 kA and a reverse voltage hold-off of 24 kV. Unlike common gaseous switches, TPI thyratrons can operate for over 20,000 h at hundreds of kHz. These devices are serious competitors to both conventional hydrogen hot cathode thyratrons and to high-power solid-state switches. TPI thyratrons are particularly advantageous in burst mode operation where direct and reverse voltages in the range of tens of kV, currents up to 10 kA, nanosecond jitter and risetimes of 1-5 ns are required.

A method for fast parallel scanning of a low-energy electron beam (scan amplitude, ± 4 cm; scan time, 10 ns; beam energy, 60 keV) is described. Results of application of this method to nondestructive diagnostics of the proton bunch are presented.

The circuit of modulator, serving to supply inductive-resistive load in double-pulse mode with currents up to 10 kA and pulse duration of 300 ns, is described. As switching components unheated cathode thyratrons (pseudospark switches) TPI1-10k/50 and TPI5-10k/50 with anode voltage up to 50 kV have been used. The results of tests, confirming possibility of the thyratron reverse dielectric strength recovery within some microseconds after switching of 10 kA forward anode current, are presented.

A method for measuring the asymmetry of the longitudinal charge distribution in an electron bunch of the ВЭПП-4М collider by an electron beam probe is proposed. The operating principle of the electron beam probe and the measuring technique are described. Interaction between the testing beam and an asymmetric relativistic bunch is simulated, and the asymmetry of the electron bunch on the ВЭПП-4 collider is measured. The main components of the error in measuring the asymmetry are determined.

A new diagnostic instrument intended for measuring the parameters of intense bunches, detecting radiation fields, and performing tomography of intense ion beams is described. The operating principle of the device and the basic scheme of arrangement of its elements are described. The results of simulation of a EBP for several problems are presented. To reconstruct the longitudinal charge-distribution function, the effect detection error of the testing beam on the accuracy of the proposed method is considered. Depending on the problem to be solved, several design versions of the instrument are proposed, which are optimized for diagnosing beams of S-range linear accelerators, detecting radiation fields, studying bunches of superhigh intensity, performing tomography of intense proton beams, and operating in cyclic accelerators.

A source of positrons allowing 5 × 108 positrons accelerated to the energy of 70 MeV to be produced per pulse has been developed. The process of electron-positron pair production in an electromagnetic shower is used for production of positrons. The electromagnetic shower is generated in a tantalum target by a beam of 2 × 1010 electrons with energy 270 MeV. A high efficiency of positron collection (positron yield Y ≈ 0.1 GeV−1) is ensured by a unique design of the matching device.

The morphology and electronic structure of 13C-isotope-based graphite composites were studied by transmission electron microscopy (TEM), x-ray diffraction, and x-ray fluorescence spectroscopy. High-resolution TEM images showed that composites contain several forms of carbon particles. According to an x-ray diffraction analysis, the size of graphene stacks of graphite particles is 20 and 40 A. The CK α x-ray fluorescence spectra of the initial 13C isotope powder and composites based on it detected an increase in the density of high-energy occupied states in comparison with the graphite spectrum. Ab initio quantum chemical calculation of the structure of C150 graphene showed that the increase in the density of states stems from the electrons of dangling bonds of boundary carbon atoms of particles ∼20 A in size. Electrical properties of 13C-isotope-based samples were studied by analyzing the temperature dependence of the conductivity. It was assumed that the change in the logarithmic dependence of the conductivity observed at liquid-helium temperatures to the linear dependence as the temperature increases is caused by carrier transfers between the disordered graphene layers forming a nanocomposite.

The unique properties of synchrotron radiation (SR) account for its wide usage into fundamental, applied and technological investigations. Large growth of the number of SR applications in technological processes and medical diagnostics has been observed recently, which makes the problem of developing compact and relatively cheap SR sources very actual. A good progress of Budker Institute of Nuclear Physics (BINP) in the field of fabrication of different superconductive devices for SR generation may give rise to a new tendency in the design of compact SR sources. Indeed, the 9 T superconducting bending magnet fabricated at BINP for the BESSY-2 storage ring is a good candidate for the main element of the magnetic structure of a compact SR machine. The development of compact hard X-ray SR source started at BINP. This work involves analysis of possible implementation of compact SR sources in industry, medicine and education. Main SR parameters meet the requirements of most popular research application methods. These parameters became a basis for determination of main parameters of storage ring and allowed us to propose a possible scheme of storage ring.

The conductivity of graphite composite samples MPG-6 and MPG-7 has been measured before and after 1.4 MeV electron irradiation and heating by alternating current up to temperatures higher than 2500°C, causing the fracture of the samples. It has been shown that both heating and electron irradiation result in a shift of the temperature dependence of the conductivity of the samples, namely, in an increase in conductivity. The measurements of the relative magnetoresistance at helium temperature in fields of ±1.15 T have shown that the imperfection of the macrostructure increases. The noticeable changes in the x-ray phase diagram do not observed up to the fracture of the samples. All the obtained data make it possible to suppose that the ultimate strength and the lifetime of graphite composites are limited by intercrystalline or grain boundaries.

A 2-MeV, 2-kA Linear Induction Accelerator LIA-2 was built and is in routine operation [1, 2]. Accelerator's high voltage system consists of 48 pulsed modulators, each of them supplies a couple of accelerating gaps with two pulses of 200 ns duration at peak voltage of 21 kV and variable delay between pulses from 2 to 100 μs. Pulse forming networks with combined dielectric and TPI-type pseudospark switches are used in the modulators. Pulsed system design is described and accelerator's four-year operation results are presented.

Prototype of a pulsed modulator for a future 20-MeV, 2-kA linear induction accelerator power supply is developed. It is capable of generating three pulses of flattop duration up to 350 ns at peak voltage 23 kV and current up to 10 kA with the variable delay between pulses from 2 to 100 μβ. TPI-type pseudospark switches with fast reverse recovery have been used that helped to simplify modulator schematics [1]. Improved diode characteristics of the pseudospark switches taken at reverse voltage up to 25 kV applied in 0.1–20 μβ after 5–10 kA forward current commutation are analyzed. Results of triple-pulse modulator operation are presented.

A 13C-based neutron-target material is investigated using x-ray diffraction, IR absorption and Raman scattering spectroscopies, transmission electron microscopy, and electrical (conductivity, magnetoresistance, and Hall effect) measurements before and after high-power electron irradiation for various lengths of time.

We have shown that triterpene glycosides of the Far Eastern edible holothurian Cucumaria japonica (monosulfated subfractions A2 and A4, disulfated subfraction A6, trisulfated subfraction A7, and the total fraction of monosulfated glycosides including subfractions A0, A1, A2, and A4) inhibited growth of the main root of Cucumis sativus seedlings. Cucumariosides were arranged as follows according to their inhibitory activity: subfraction A2 (ED50 = 53.1 ± 3.6 μg/ml) > total fraction of monosulfated glycosides (ED50 = 127.4 ± 5.8 μg/ml) > subfraction A4 (ED50 = 346.5 ± 15.2 μg/ml) > subfraction A6 (ED50 = 375.7 ± 17.2 μg/ml) > subfraction A7 (ED50 = 539.4 ± 11.5 μg/ml). The average length of the main root decreased with the increase of glycoside concentrations as a result of a growing amount of seedlings with low germination capacity and the absence of seedlings with high germination capacity.

We studied the effect of extractive substances (ES) and total glycoside fraction (TGF) from Panax ginseng on plant cell growth. The seeds of cucumber Cucumis sativus L., KIT variety, were used for the biological assay. The tested substances inhibited the primary root growth in Cucumis sativus seedlings. Actively growing seedlings were most sensitive to this effect.

The VEPP-5 injection complex under construction at the Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences is a powerful source of intense electron and positron bunches at 510 MeV, which covers all needs of the electron–positron colliding beam setups currently operating and under construction at the Institute of Nuclear Physics. The complex includes a 285 MeV linear electron accelerator, a 510 MeV linear positron accelerator, and an accumulator–cooler with beam injection and ejection channels. Intense work on the design, assembly, and tuning of the linear electron accelerator has been conducted in the last 2 yr. As a result, by August 2002 the linear electron accelerator was put into operation with all standard subsystems. By this time, the isochronous achromatic turning of the electron beam, a system for converting electrons into positrons, and the first accelerating structure of the linear positron accelerator were assembled and put into operation. All this made it possible to accelerate the positron beam up to 75 MeV. Preliminary results of tests of the linear accelerators are presented.

The laser wakefield acceleration (LWFA) of electrons in capillaries and gas jets followed by inverse Compton scattering of high intensity femtosecond laser pulses is discussed. The drive and scattered pulses will be produced by the two-channel multi-terawatt laser system developed in ILP SB RAS.

Estrogens play the most important role in breast cancer oncogenesis. There are different methods used to decrease estrogen production and serum concentration: surgery, irradiation and drug-based method. In the current study 500 patients with localized surgically resectable breast cancer (infiltrative-edematous form included) or disseminated breast cancer with indication for ovarial function inhibition. The patients were divided into 3 groups. The first group consisted of 400 patients with prior endoscopic bilateral ovariectomy. The second group included 50 patients with prior ovarian irradiation, the third one included 50 patients after laparotomic ovarian resection. The results obtained show 100% effect of endoscopic ovariectomy resulted in disabled ovarian function, which is more effective, than ovarian irradiation (92%). Besides, the endoscopic method doesn't have negative effects characteristic for irradiation, such as involvement of non-target organs or restoration of hormone production. Endoscopic surgery was characterized by 10-fold decrease in complications rate compared to laparotomic operation (2.2% vs 24%). Besides, endoscopic intervention leads to much shorter inpatient treatment duration and demand for anesthetics and antibiotic treatment making it less costly, than more traditional methods of castration. Therefore, endoscopic ovarian resection is a safe and effective castration method in breast cancer patients.

Summary form only given. A modulator circuit providing for supply of inductive-resistive load in double-pulse mode with currents up to 10 kA and pulse duration of 300 ns is described. As switching components thyratrons (pseudospark switches) TPI1-10k/50 with anode voltage up to 50 kV are used. In contrast with other pseudospark switches TPI-thyratrons are capable of operating in circuitry with grounded cathode which allows a service life time up to 20,000 hours. The thyratrons can be considered as an alternative to well-known switches, including hot cathode hydrogen thyratrons and up-to-date power solid state switches, especially for switching of high-currents with sub-nanosecond jitter, turn-on time of 3-5 ns and average current up to 0.3 A. The absence of hot cathode provides in thyratron more homogeneous distribution of gas density and hence shorter turn-on time. Simultaneously it simplifies thyratron design, removes additional power supply and source of heat. There is no need for forced cooling. This new design allows operation without cathode heating and, which is more valuable, without hydrogen reservoir heating. This significantly simplifies auxiliary circuits up to a level of spark gaps. Results of tests, confirming the possibility of reverse dielectric strength recovery within some microseconds after switching of 10 kA forward anode current are presented. Basic electrical parameters affecting thyratron operation in the indicated mode are analyzed. A pentode version of the thyratron, which allows for a reduced recovery time up to 0.5-1 mus is designed and will be presented.

A study was made of the ultrastructure of root cap meristematic cells in the seedlings of Cucumis sativus L., whose growth was inhibited by the action of 2-acetyl-4-metylcyclopent-4-en-1,3-dione (AMCD). It is shown that the treatment of seeds by this substance at a concentration of 100 microg/ml leads to the main root inhibition by 73% and, as compared to the control, causes the highest changes in mitochondria that do not reach normal dimensions and undergo degeneration. AMCD caused significant changes in the cell walls that in test samples unusually became electron-dense. Deposits of osmiophylic substance, presumably consisting of terpenoid-like compounds, were often found in the cytoplasm of treated cells as well as in the extracellular space. In many cells, plasmalemma and amiloplast membranes underwent destructive changes. We discuss a possible relation between inhibitory effect of AMCD on the root growth, and its influence on the ultrastructure in investigated cells.

The paper presents some conclusions on about the interference stability of medical engineering products, which have been made on the tests for requirements for electromagnetic compatibility of different kinds of products--from the simplest to the most elaborate life-support systems. It gives a list of basic standards for interference stability, as well as criteria for the quality of operation of the products tested for the stability.

The paper considers requirements for noise immunity of medical equipment, types of electromagnetic disturbances, and a list of medical apparatuses intended for obligatory certification testing for noise immunity. The paper presents experimental data on the impact of electromagnetic disturbances on different types of medical apparatuses.

When boiled with phosphorus pentachloride in phosphorus oxychloride, 2-methyl-6-phenyl-imidazo[1,2-b]1,2,4-triazin-4H-3-one gives a mixture of mono- and dichloro derivatives, whereas the action of thionyl chloride in chloroform with a catalytic amount of DMFA gives only the monosubstituted product 2-methyl-3-chloro-6-phenylimidazo[1,2-b]-1,2,4-triazine. The reactivity of the 3-chloro derivatives of imidazo[1,2-b]-1,2,4-triazine in reactions with diethylamine, piperidine, morpholine, aniline, hydrazine hydrate and thiourea was investigated.

Refluxing 1,2-diaminobenzimidazole with 3-benzoyl-2-propanonic acids in methanol gives the corresponding salts, viz., 1,2-diaminobenzimidazole 3-benzoyl-2-propanonates, which are converted to 2-benzoylmethyl-1,2,4-triazino[2,3-α]-benzimidazol-4H-3-ones upon heating in high-boiling organic solvents.

Die 1-Acylmethyl-2-chlorbenzimidazole (I) reagieren mit Hydrazinhydrat oder Hydrazinen (II) uber die Zwischenstufe des Hydrazons (III) zu den Triazinobenzimidazolen (IV).