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Objectives. The formalized problem of the optimal design of distillation column systems belongs to the class of mixed integer nonlinear program problems. Discrete search variables are the number of trays in the rectifying and stripping sections of columns, whereas the continuous ones are the operating modes of columns. This study aimed to develop an algorithm and a software package for the optimal technological design of a system of simple distillation columns based on the criterion of total reduced capital and energy costs using rigorous mathematical distillation models.Methods. The solution to this problem is based on the branch and bound method. A computer model of the distillation column system was developed in the environment of the Aspen Hysys software package. The Inside–Out module was used as the distillation model. The developed algorithm is implemented in the software environment of the Matlab mathematical package. To solve the conditional optimization problem, a sequential quadratic programming method-based model was used. The interaction between software add-ins in Matlab and Aspen Hysys is implemented using a Component Object Model interface.Results. Approaches to obtain the lower and upper bounds of the optimality criterion and the branching method for the implementation of the branch and bound method have been developed. In addition, an algorithm for the optimal design of a distillation column of a given topology based on the branch and bound method has been developed. Furthermore, using Matlab, a software package that implements the developed algorithm and is integrated with the universal modeling software AspenHysys has been created.Conclusions. An algorithm and a software package have been developed and implemented that allows automating the design process of distillation column systems and integration with advanced mathematical programming packages, respectively. The performance of the algorithm and software package has been evaluated using the optimal design of the debutanization column as an example.

Physical and engineering aspects of RF plasma cleaning developed for actively cooled first mirror serving as grounded DC-coupled electrode are under consideration. Feasibility of the water-cooling lines implemented as the coaxial notch filter for ITER in-vessel diagnostic mirrors was demonstrated for Capacitively Coupled Radio Frequency (CCRF) discharge in neon at 1–10 Pa. The impinging ions energy as a function of absorbed RF power was measured for both the DC-coupled and -decoupled schemes. Sputtering yield variation over rectangular surface of stainless steel mirror was studied experimentally. The measured sputtering yield profiles were found to be in qualitative agreement with the RF plasma numerical simulations. It was demonstrated that Al/Al2O3 used as Be/BeO proxy can be removed from the water cooled mirror surface by 100 eV neon ions with the use of the notch filter. The 14 h plasma exposure didn’t affect the mirror reflectivity.

The local measurements of electron density and temperature by Thomson scattering (TS) diagnostics are essential for research of energy confinement, plasma heating, and control at nuclear fusion devices. This paper presents a digital filter polychromator designed for TS spectrum registration. A distinguishing feature of such a digital polychromator is the use of an analog-to-digital converter (ADC) having analog memory with discretization frequency of 5 GHz and 12-bit sampling. The low heat dissipation and compact design of the ADC allow us to integrate the recording and data handling systems in the spectral unit to obtain a standalone device that is totally isolated from other systems and equipment in the voltaic sense. The scattered laser radiation received from the plasma comes to the entrance of the polychromator through a fiber-optic cable, and the processed scattering signals and calculated electron density and temperature are available on a digital interface. The polychromator was tested within the Thomson scattering system at the Globus-M tokamak using two probing lasers: Nd:YAG 1064 nm and Nd:Glass 1055 nm operating with pulse energy up to 2J and FWHM of 4 and 40 ns, respectively. The employed ADCs allowed us to perform superfast signal digitizing in the oscilloscope mode and to demonstrate the possibility of stray signal time separation despite the modest size (~1 m) of the vacuum chamber. The results of measurements performed during the plasma experiment at the Globus-M tokamak are presented, and their comparative analysis with the data obtained at the operating TS system is made.

The ITER divertor Thomson scattering (TS) system has been significantly upgraded in the last few years in terms of equipment and experimental setup design. In this paper, we are focusing on lasers, digital filter polychromator and piezo actuators, which could be also useful for other diagnostics. Capabilities of the probing and calibration lasers are specified and compared against ITER requirements. Key features of the digital polychromator design for TS applications are presented and obtained signal-to-noise ratios are discussed. The main reason to use piezo actuators for in-vessel remotely controlled devices is high radiation and magnetic resistance of piezo elements. Piezo actuators of inertial and ultrasonic types were produced and their promising performance for fusion devices was demonstrated.

ITER (International Thermonuclear Experimental Reactor) is a nuclear fusion research and engineering project. It is supposed to be the first fusion device to test the integrated technologies, materials and operational regimes necessary for the commercial production of fusion-based electricity. Front (explored in this paper) and Back diagnostic racks are used as supporting structures of the so-called ITER Divertor Thomson Scattering (DTS) Diagnostic System that is created to measure plasma characteristics. They will be attached to the lower port walls (ITER ports are used to locate diagnostic equipment and its supporting structures) through the so-called Divertor Rails. The developed design of the Front (Diagnostic) Rack locking (e.g. Rack attachment to the rails mechanism) was analyzed in this research to be consistent with thermal stresses, electromagnetic and seismic loads taking into account some specific assembly and maintenance loads including preloading under installation. The analysis of the rack locking design's resistance to the mentioned loads should prove correspondence of the suggested common rack design with the structure integrity criterions. Construction strength under the most severe loading scenario was estimated in this research and appropriate conclusions were made. It was found out that the stress criterion was not fully satisfied, so a new rack locking design concept was proposed. Its main details are also described at the end of this article.

The LabBot Framework project is intended to implement control of experiment and data acquisition without writing special platform codes, while achieving industrial-grade results. The Framework is intended for fast and advanced development of controlling and data acquisition software for laboratory-scale experimental setups; more sophisticated software for middle-scale laboratory equipment; industrial-grade software for self-made commercial instrumentation developed by small- and middle-scale companies. The paper presents review of the Framework top-level architecture and its implementation addressing development of ITER Divertor Thomson Scattering (DTS) diagnostic. The first examples of the Framework implementation include the set-ups for vacuum heating testbench; RF cleaning of diagnostic mirrors as well as DTS equipment, which must be controlled by the ITER CODAC system.

The paper describes the digital filter polychromator developed for Thomson scattering (TS) diagnostics. The device having ultra-low noise, high-speed detection system and up to 7 spectral channels is equipped with digitizer and single board computer for system control and data processing. The data acquisition system is capable to detect very short laser pulses of few ns width with low magnitude. This feature opens up new possibilities for the TS diagnostics design in modern fusion devices, which includes: operation with high background illumination, measurement of very low electron temperature and density at the plasma edge and scrape-off layer (SOL), separation of the TS signal and the stray light coming with a delay of several ns. The analysis of the TS signal waveform also gives a possibility to distinguish the TS and Mie scattering from the dust particles that is important for measurements in SOL. Owing to compactness and ultra-low energy consumption both optical and data processing units interfaced with optical Gigabit Ethernet were combined in a stand-alone device. Such all-in-one design with optical fiber input and optical digital output provides enhanced resistance to electromagnetic disturbances and simplify operation. A set of such polychromators can be mounted in a standard 19” rack and can be integrated with outer CODAC (Control, Data Access and Communication) system. Testing of the polychromators at the Globus-M2 tokamak has shown excellent performance of the developed serial devices.

The possibility of double spectral conversion of UV radiation from the spectral range of 240–280 nm to the visible spectral region using luminescent glasses and fibers with antimony ions and molecular silver clusters is shown. Planar and fiber prototypes of UV radiation dosimeters are tested. It is shown that the sensitivities of dosimeter of the first and second types are 1400 and 360 mV/W/m2, respectively.

This note is devoted to a filter polychromator combining built-in optical, data acquisition and processing subsystems designed for electron temperature and density measurements in fusion plasma by Thomson scattering (TS). Special attention is paid to assessing the accuracy of TS signals measured in the polychromator spectral channels. The potential for estimating TS error caused by background emission is demonstrated using high-pass signal. The recent polychromator tests have shown APD gain stabilization better than ± 0.5% over the ambient temperature range from 17.5 °C to 35 °C

A complex of measures that utilize gas-dynamics effects for passive protection of optical elements, which are positioned deep in the diagnostic channels in the region of the ITER divertor, is considered. The proposed control methods are considered using an example of protection of optical elements for diagnostics of Thomson scattering at the ITER-tokamak divertor. To suppress the diffusive propagation of impurities, it is proposed to use the sorption properties of the walls of the diagnostic channels via an increase in their area. The presented experimental results are compared to the results of numerical calculations that confirm the efficiency of the proposed method. To suppress the convective propagation of impurities, it is proposed to use additional walls of the channel with a geometry that determines separation and deflection of flows and diaphragms for hydraulic deceleration of gas flows.

Thomson scattering (TS) is the most accurate and useful method of measuring plasma electron temperature and density in fusion-oriented experiments. The small power (∼10−8W) and short duration (∼10 ns and less) of scattering signal are the main technical problems of the method. That is why highest requirements are made to photodetection and recording systems. Developed by Budker Institute of Nuclear Physics (Novosibirsk, Russia) fast DAQ system allows recording profiles of short duration (3-5 ns) scattered pulses in 0-200MHz bandwidth with 2GSPS rate and 12-bit resolution. The system consists of photo detector modules (with 200MHz bandwidth), fast (2GSPS) and slow (10MSPS) ADC modules and synchronization subsystem. The 48-channel version of this system was developed as a prototype for ITER (Cadarache, France) divertor Thomson scattering diagnostic. The system was tested and put into operation on GLOBUS-M tokamak (St. Petersburg, Russia).

Meadow-chernozemic and dark chernozem-like meadow soils predominate on the Zeya-Bureya interfluve. The soil cover pattern of this interfluve is described in terms of elementary soil areas (ESAs) and soil combinations (SCs). The typification of elementary agricultural areas on the basis of major characteristics of the ESAs and SCs and the ways of their rational management are suggested. It is shown that most of the regional soils require phosphorus fertilizers and liming; agromeliorative and hydromeliorative drainage measures should be implemented on vast areas to improve soil productivity.

As the internationalization of universities has grown in importance, there is an increasing number of cooperative programsbetweenU.S.universitiesandthoseinothercountries.To have the most effective programs, it is important to have an understanding of the differences between the respective higher education systems. With the disintegration of the former Soviet Union there has been an increasing interest in collaborating with higher education institutions in Russia and other countries of the newly independent states. A comparison of U.S. agricultural higher education and that of Russia shows substantial differences in operation and educational philosophy. Since the higher education systems of the newly independent states were modeled after the Russian system, these comparisons provide a basicunderstandingoftheagriculturalhighereducationsystem in all of the newly independent states. The objectives of this paper are to (i) compare the structure of agricultural higher education in the USA and Russia, (ii) highlight the differences in the two systems, and (iii) identify aspects of each system that couldstrengtheneachother.Althoughchangeshaveoccurredin theRussiansystem,additionalchangesmightinclude:permitindividual universities to set their own student/faculty ratios, determine student enrollment, charge tuition to all students, and grant them freedom to develop their own curricula.

D-glucuronyl C5-epimerase (GLCE) is one of the key enzymes in proteoglycan biosynthesis. However, nothing is known about expression and activity of the protein in cancer. In this study, we investigated GLCE expression in human breast cancer using multipex RT-PCR, QRT-PCR and Western-blot assays. In total, 21 patients without malignancy and 74 patients with breast tumor were investigated. The obtained data showed that in 82-84% of human breast tumors there is either downregulation or loss of D-glucuronyl C5-epimerase mRNA expression and significant decrease of the protein content. In most cases (77%), GLCE expression was decreased also in the normal-appearing tissue surrounding the tumor node but the protein amount was comparable to normal breast tissue. These findings represent the first data about involvement of human D-glucuronyl C5-epimerase in malignant transformation.

Almost all optical diagnostic systems in ITER will require the implementation of mirror recovery and protection systems. Plasma cleaning is considered to be the most promising technique for the removal of metal deposits from optical surfaces. The engineering and physical aspects of RF discharge application for continuous or periodic plasma treatment are discussed with a focus on implementation under ITER conditions. The ion flux parameters obtained in capacitively coupled (CC) RF discharge were measured in the mock-up of a plasma cleaning system. The uniformity of sputtering in CC RF discharge with and without a magnetic field was studied experimentally for the cylindrical discharge reactor geometry and compared with numerical simulations. The sharp increase in the sputtering rate resulting from the non-uniform radial distribution of the ion flux was observed near the electrode edges. The longitudinal magnetic field improves sputtering uniformity. It was demonstrated that Al/Al2O3 deposits can be removed in the Ne and D2 plasma of CC RF discharge but long-term exposition results in the degradation of the polycrystalline molybdenum mirror surface. The efficiency of Al sputtering in the atmosphere containing O2 and N2 fractions was studied in the D2/O2 and D2/N2 plasma of glow discharge. The addition of 2% of oxygen or nitrogen increases the sputtering yield by 3–4 times as compared with that in a nominally pure D2 discharge. The impact of metal deposits on the performance of diagnostic mirrors is discussed. It was shown that an ultrathin metallic film with a thickness as low as a few nm may cause a significant degradation of diagnostic mirrors with a transparent coating.

The electron component is the main channel for anomalous power loss and the main indicator of transient processes in the tokamak plasma. The electron temperature and density profiles mainly determine the operational mode of the machine. This imposes demanding requirements on the precision and on the spatial and temporal resolution of the Thomson scattering (TS) measurements. Measurements of such high electron temperature with good accuracy in a large fusion device such as ITER using TS encounter a number of physical problems. The 40 keV TS spectrum has a significant blue shift. Due to the transmission functions of the fibres and to their darkening that can occur under a strong neutron irradiation, the operational wavelength range is bounded on the blue side. For example, high temperature measurements become impossible with the 1064 nm probing wavelength since the TS signal within the boundaries of the operational window weakly depends on Te. The second problem is connected with the TS calibration. The TS system for a large fusion machine like ITER will have a set of optical components inaccessible for maintenance, and their spectral characteristics may change with time. Since the present concept of the TS system for ITER relies on the classical approach to measuring the shape of the scattered spectra using wide spectral channels, the diagnostic will be very sensitive to the changes in the optical transmission. The third complication is connected with the deviation of the electron velocity distribution function from a Maxwellian that can happen under a strong ECRH/ECCD, and it may additionally hamper the measurements. This paper analyses the advantages of a 'multi-laser approach' implementation for the current design of the core TS system. Such an approach assumes simultaneous plasma probing with different wavelengths that allows the measurement accuracy to be improved significantly and to perform the spectral calibration of the TS system. Comparative analysis of the conservative and advanced approaches is given.

A divertor Thomson scattering (TS) system being developed for ITER has incorporated proven solutions from currently available TS systems. On the other hand any ITER diagnostic has to operate in a hostile environment and very restricted access geometry. Therefore the operation in an environment of intensive stray light, plasma background radiation, the necessity meet the requirement using only a 20 mm gap between divertor cassettes for plasma diagnosis as well as to measure plasma temperatures as low as 1 eV severely constrain the divertor TS diagnostic design. The challenging solutions of this novel diagnostic system which has to ensure its steady performance and also the operability and maintenance are the focus of this report. One of the most demanding parts of the in-vessel diagnostic equipment development is the design assessment using different engineering analyses. The task definition and first results of thermal, e/m and seismic analyses are provided. The process of further improving of the design involves identification of susceptible areas and multiple iterations of the design, as needed. One of the key points for all Thomson scattering diagnostics are the laser capabilities. A high-performance and high-power laser system using a steady-state and high-repetitive mode Nd:YAG laser (2J, 50–100Hz, 3ns) has been developed. The reduced laser pulse duration matched with high-speed low-noise APD detector can be very important under high background light level. For diagnostics such as Thomson scattering and Raman spectroscopy, a high-degree of discrimination against stray light at the laser wavelength is required for successful detection of wavelength-shifted light from the laser-plasma interaction region. For this case of high stray light level, a triple grating polychromator characterized by high rejection and high transmission has been designed and developed. The novel polychromator design minimizes stray light while still maintaining a relatively high transmission.

We present here our recent results on the development and testing of the first mirrors for the divertor Thomson scattering diagnostics in ITER. The Thomson scattering system is based on several large-scale (tens of centimetres) mirrors that will be located in an area with extremely high (3–10%) concentration of contaminants (mainly hydrocarbons) and our main concern is to prevent deposition-induced loss of mirror reflectivity in the spectral range 1000–1064 nm. The suggested design of the mirrors—a high-reflective metal layer on a Si substrate with an oxide coating—combines highly stable optical characteristics under deposition-dominated conditions with excellent mechanical properties. For the mirror layer materials we consider Ag and Al allowing the possibility of sharing the Thomson scattering mirror collecting system with a laser-induced fluorescence system operating in the visible range. Neutron tests of the mirrors of this design are presented along with numerical simulation of radiation damage and transmutation of mirror materials. To provide active protection of the large-scale mirrors we use a number of deposition-mitigating techniques simultaneously. Two main techniques among them, plasma treatment and blowing-out, are considered in detail. The plasma conditions appropriate for mirror cleaning are determined from experiments using plasma-induced erosion/deposition in a CH4/H2 gas mixture. We also report data on the numerical simulation of plasma parameters of a capacitively-coupled discharge calculated using a commercial CFD-ACE code. A comparison of these data with the results for mirror testing under deuterium ion bombardment illustrates the possibility of using the capacitively-coupled discharge for in situ non-destructive deposition mitigation/cleaning.