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The Kupol epithermal Au-Ag vein district is located in the northern part of the Okhotsk-Chukotka volcanic belt, a Late Cretaceous subduction-related continental volcanic arc exposed for >3,000 km along the eastern coast of Russia. High-grade veins are hosted in the Kupol andesite sequence, a 300- to 1,000-m-thick, subhorizontal, layered sequence of andesite flows, sills, and ash tuffs, dated at 97 to 96 Ma (Cenomanian). The Kupol andesite sequence is underlain by mixed mafic-felsic volcanic units plus sedimentary rocks (“older volcanics”) and overlain by a >1-km-thick “upper felsic” sequence of dacitic-rhyolitic tuffs and associated dikes and flow domes, dated at 95 to 85 Ma, with local sequences of fluvio-lacustrine sedimentary rocks. The epithermal veins occupy N-striking, steeply dipping normal faults that cut thick coherent andesite flows and sills in the central-upper part of the Kupol andesite sequence. The district is dominated by the large Kupol vein (180.7 tonnes (t) Au and 1,986 t Ag produced to 2020), hosted by the 5.5-km-long Kupol fault, which accommodates normal, east-side-down displacement of up to 190 m. The Moroshka and Providence veins, 5 km east-southeast of Kupol, occupy shorter faults (1- to 2-km strike) with smaller vertical displacements (to 70 m). The Moroshka vein is dated at 93.5 ± 1.5 Ma (Turonian; 40Ar/39Ar method on adularia), and the timing of vein mineralization here and at Kupol overlaps with the early stage of upper felsic sequence magmatism. Veins contain subhorizontal ore shoots, controlled by the intersection of the steep faults with flat-lying Kupol andesite sequence stratigraphy and by steepening of the faults to a more dilational orientation as the inferred paleosurface is approached. Local structural controls are also evident, reflecting a component of oblique slip on the Kupol fault, with the thickest vein segments at steeply pitching jogs and relays. Main-stage veins grew via repeated encrustation by quartz-chalcedony ± amethyst ± lattice bladed calcite (replaced by quartz), with Au-Ag–bearing crustiform adularia ± clays ± sulfides/sulfosalts/electrum ± chlorite ± hematite bands. The main controls on Au grade are inferred to have been boiling, resulting in sharp vertical limits to high metal grades typical of epithermal veins, coupled with optimal dilation of the vein system where the hosting normal fault steepens near surface with decreasing differential stress. Although much of the displacement on the controlling faults is pre-mineralization in timing, lithified cataclastic breccia, coeval with some vein stages, and vein geometry patterns indicate that some vein development occurred contemporaneously during late normal displacement along the fault system. Waning of the hydrothermal system is marked by late carbonate fill, initially Fe dolomite, then coarse calcite as veins, matrix to vein breccia, and central vein cavity fill. The Kupol district veins have proximal adularia-quartz alteration (haloes meters wide), within an extensive (hundreds of meters in scale) clay alteration halo. Clays are zoned both vertically and laterally with respect to veins, with inner illite-chlorite that was magnetite-destructive (at highest paleotemperature; >220°C), grading outward and upward to illite/interlayered illite-smectite with kaolinite, then to an outer zone (or upper blanket) of smectite, at lowest paleo-temperature (

The results of computational and experimental studies of a model of a hypersonic convergent air intake are presented. Experimental studies were carried out in a hot-shot wind tunnel IT-302M SB RAS at a Mach number M = 5.7 and an angle of attack α = 4 °. Numerical modeling was carried out in a three-dimensional setting in the ANSYS Fluent software package. The calculations were carried out in 4 versions using different turbulence models: k-ɛ standard, RNG k-ɛ, k-ɷ standard and k-ɷ SST. The features of the flow structure are established. The pressure distributions on the compression surfaces and in the air intake channel are obtained. The separated flow at the entrance of the inner channel was studied. It was found that the use of various turbulence models has a significant effect on the size and position of separation. The best agreement between the calculated and experimental data on the level of static pressure was shown by the variant with the k-ɛ standard turbulence model.

Current retinal prostheses (RPs) have not achieved useful vision restoration, as their resolution is limited by power dissipation and complexity of interconnect. This article presents an inductively powered wireless system on a chip (SoC) for an electrically controlled, optically addressed retinal prosthetic system. The SoC interfaces to a co-fabricated nanoengineered photosensitive electrode array using only two wires. To reduce the thermal dissipation near sensitive retinal tissue, the proposed design pushes voltage regulation and charge-balanced stimulation control off the implant via a duty-cycled wireless charge metering technique. A calibration technique compensating for power fluctuation caused by eye movement is also presented. Implemented in 180-nm CMOS and delivering up to $3~\mu \text{C}$ of charge at 20-nC resolution, the SoC achieves 73% RF-to-stimulation power efficiency.

High-grade epithermal Au–Ag veins of the Vodorazdelnaya district in far eastern Russia are hosted by Early Cretaceous volcanic rocks of the Tytylveem belt. The largest deposit is Zone 37, a 1-km long, northeast-striking vein that is up to 35-m wide, containing at least 32 t Au. The main shoot consists of crustiform—colloform banded quartz-chalcedony-adularia-sulfide veins, of low-sulfidation style. The vein is cut by late-mineral rhyolite sills and dikes. Zone 37 vein is dated at 117 ± 2 Ma, overlapping within error with the cross-cutting rhyolites (121–119 Ma) and with intrusions of the nearby Ilirney granitic pluton (119–117 Ma). The volcanic host rocks are dated at 121–115 Ma. At September Northeast, 15 km west-northwest of Zone 37, mineralisation consists of veins up to 4 m wide, with crustiform banded quartz ± chalcedony ± adularia ± chlorite, and Zn-Pb-Cu sulfides, of intermediate sulfidation style, in a 1-km-long, north-northeast striking trend. High grades are associated with gold dendrites in fine-grained quartz bands and with minor late-stage tellurides. The veins were disrupted by intrusion of rhyolite dikes and associated phreatic breccias. Some breccias host mineralisation as vein clasts and minor matrix sulfides. The Tytylveem belt is preserved below a regional unconformity that forms the base to the overlying Late Cretaceous (106–77 Ma) Okhotsk-Chukotka Volcanic Belt (OCVB). Intrusive rocks attributed to OCVB magmatism were emplaced at about 96 Ma and are associated with overprinting hydrothermal alteration, sub-economic veins and thermal resetting of some vein adularia ages at Zone 37, to 91–97 Ma.

First data on oxygen isotopic composition in phenocrysts in volcanic rocks from Okhotsk–Chukotka volcanic belt (106–78 Ma, North-Eastern Russia) together with Sr and Nd isotopic data gives additional geochemical evidence on belt segmentation. Calculated δ18Omelt in calc-alkaline magmas of belt vary from normal-δ18O (from +5.2 to +6.9‰) consistent with mantle-like signatures of radiogenic isotopes. Low-δ18O (from +4.7 to +4.8‰) silicic magmas were found in Western–Okhotsk segment of the belt interpreted as assimilation of hydrothermally altered rocks from pre-caldera rifted basement. The highest δ18O values were obtained for Chukotka segment of the belt reaching +10.8‰ and these are correlated with elevated 87Sr/86Sr due to assimilation of relatively mature high-δ18O continental crust. Comparison with Kamchatka volcanic belt is performed.

The article presents new data on geology, mineralogy, and geochemistry of porphyry-copper, gold-silver, and silver-polymetallic ore occurrences in the Kongin magmatic zone of the Omolon terrane and granitoids, associated with it. It has been demonstrated that petrology and the age of granitoids are similar to those in the OCVB Penzhina segment. Mineralization of the Kongin zone is very close to that of the OCVB, differing in relatively high Mo in porphyry-copper ores and prevalence of silver-polymetallic mineralization over gold-silver.

The statistics is presented in the article concerning the industrial explosives consumption in the world and in the Russian Federation, based on which it is possible to estimate the scale of emission of toxic gaseous explosion products into the environment. The mechanism of formation of gaseous explosion products depending on the oxygen balance of the mixed ammonium nitrate explosive is briefly outlined. In the methodological part of the work, an overview is made related to some computational methods for determining the qualitative and quantitative compositions of gaseous explosion products of industrial explosives based on ammonium nitrate. The main regularities of the influence of physical and physicochemical factors surrounding the charge of an industrial explosive on the formation of toxic gaseous explosion products are described. Computational part of the work is a description of the calculation parameters and the used software packages Shock and Detonation and Real, and the tabulated results of the calculations in comparison with the experimental data obtained from the literature sources. When discussing the results, it is shown that using theoretical calculation methods, only an approximate estimate (with an error of more than 32 %) of the qualitative and quantitative compositions of gaseous explosion products is possible. Doubt is expressed about the conversion coefficient of the concentration of nitrogen oxides to the conditional carbon monoxide-6.5, which is adopted for use in the calculations without substantiating the reasons. It is concluded that only computational methods for determining the composition of gaseous explosion products are available, the results of which are far from reality, and experimental methods are only partially close to the real conditions, respectively, it is required to develop new computational methods. It is noted that the prospect for the development of this topic is the creation of a new computational software package based on the experimental data.

Given the upward trend of deforestation in the world, improving the quality of wood waste sorting operations is a major challenge in forestry from the perspective of energy saving and environmental...

n this paper, the frequency characteristics of a special brushless magnetoelectric motor of return-rotary motion with sinusoidal and rectangular forms of the carrier signal are investigated. The method of generating a feedback signal on the amplitude of the rotor shaft oscillations angle has been improved by fixing the value of the signal at the moment of reaching its amplitude. The method of calculating the control system of the oscillations angle amplitude is investigated based on the frequency characteristics of the open-loop system by setting the phase stability margin. Examples of the calculation of transient processes of regulation of the oscillations angle amplitude and the effective value of the stator current when starting the motor and changing the mechanical load are given. References 9, figures 6, tables 2.

The experimental verification of the calculated flash point temperatures of solvent mixtures used in industry is presented, and the evaluation of the adequacy of the methods for calculating the rate of its evaporation is given. To verify these methods, acetone-benzene and acetone-chloroform mixtures were experimentally studied, for which a deviation from Raoult's law could be assumed. The dependences of the evaporated substance on time at room temperature are obtained. An increase in the saturated vapor pressure and an increase in the evaporation rate are observed in the first mixture, and a decrease in the second. In the first case, the amount of substance that is taking part in the explosion increases and must be taken into account when calculating the room pressure increase during explosion, and the second can be used to reduce the potential explosive hazard of solvent mixtures. The problem of predicting fire and explosion hazard of solvents is associated with the identification of the fact of the formation of explosive concentrations of their vapors and change of flash point temperatures of the mixed liquids. By the example of a number of binary mixtures of flammable liquids, the influence of the interaction of their components on the flash point is shown, the calculated and experimental (reference) data in a closed crucible are compared for the ratio of components in the range from 0 to 100 % in benzene-toluene and benzene-ethanol mixtures. It is noted that for mixtures with a similar molecular structure, the results of calculating the flash point are in good agreement with the experiment, otherwise, the calculation gives overestimated values for liquids of various classes. Therefore, for mixtures of solvents used in industry, the number of components of which is three or more, it is required to check the flash point experimentally in order to more accurately predict their fire and explosion hazard.

A possibility of using hardening treatment of the stamping tools in high-pressure nitrogen with thermal cycling was analyzed. A thermal field of Kh12MF steel batches under accelerated heating and cooling conditions during thermal cycling was studied. A satisfactory agreement between the experimental and prescribed temperature conditions in the central and peripheral batch regions has been established. A thermal cycling with subsequent quenching was shown to have a positive effect on the structure, hardness, and impact toughness of steel.

Subject. Shared-equity investment in the primary housing sector is one of the most popular vehicles to finance housing construction projects. Objectives. We identify and analyze positive and negative aspects for co-investors of housing development projects in using escrow accounts. The article analyzed issues and possible solutions resulting from the innovative interaction of parties to housing construction projects in Russia. Methods. Studying the use of escrow accounts as a mean to make the finance of housing construction projects legally secure, we apply methods of logic, statistical and comparative analysis. Results. The article indicates positive and negative aspects of using escrow accounts and enlists risks associated with the purchase of housing when its construction is in progress. We describe how individual co-investors can protect their invested funds. We suggest the escrow account mechanism should be more thoroughly elaborated to secure the finance of housing construction projects. Conclusions and Relevance. The facility is novel for Russia. People are very wary of such innovations, especially in the housing segment. Would-be buyers should have clearer information about changes in the housing purchase procedure. Co-investors should be explained what requirements they need to meet when choosing a lending institutions and a developer, documentation on a shared-equity construction. It is crucial to communicate all details and technicalities about negative aspects of the financial facility.

The article deals with the subject, system and sources of trade (entrepreneurial) law in the aspect of the international space. The author of the article notes a significant practical connection between international business and international private law, names their main features as a dispositive method of legal regulation, independence and equality of subjects of civil legal relations, the presence of corresponding rights and obligations among the subjects of such relations, a pronounced property nature of the civil liability of subjects.

New data are obtained on the age of the epithermal gold-silver mineralization of the Kubaka deposit (Omolon Massif, Northeast Russia). Our geological observations in the open-pit mine of the Zokol zone of the deposit allow us to conclude that the mineralization formed between the eruptions of Upper Devonian ore-hosting volcanites of the Kedon series (zircon U-Pb age ~ 370 ± 2.5 Ma, SHRIMP) and Lower-to-Middle Jurassic trachybasalts and picrobasalts of the Omolon Complex (40Ar/39Ar plateau age of 179 ± 8 Ma) without the vein penetrating into the Carboniferous Corba Formation. The 40Ar/39Ar plateau age for a white adularia from the productive quartz vein yielded 299 ± 3.5 Ma (MSWD = 0.91, p = 0.43, 66% of 39Ar released in four steps). Our results contradict a commonly accepted concept of “polychronous” ore formation (during the Carboniferous and Cretaceous) or long-term mineralization at the Kubaka deposit, and likely indicate a high probability of at least an Upper Carboniferous upper age limit of epithermal gold mineralization.

In this paper we present the results of the design and production of an air-cooled X-band solid-state power amplifier based on AlGaN/GaN/SiC Schottky FET. The power amplifier includes: preliminary power amplifier, output power amplifiers, set of secondary power supplies, digital control unit, monitoring system for the power amplifier performance, set of microwave power waveguide combiners.

Dropout and DropConnect are known as effective methods to improve on the generalization performance of neural networks, by either dropping states of neural units or dropping weights of synaptic connections randomly selected at each time instance throughout the training process. In this paper, we extend on the use of these methods in the design of neuromorphic spiking neural networks (SNN) hardware to improve further on the reliability of inference as impacted by resource constrained errors in network connectivity. Such energy and bandwidth constraints arise for low-power operation in the communication between neural units, which cause dropped spike events due to timeout errors in the transmission. The Dropout and DropConnect processes during training of the network are aligned with a statistical model of the network during inference that accounts for these random errors in the transmission of neural states and synaptic connections. The use of Dropout and DropConnect during training hence allows to simultaneously meet two design objectives: improving robustness of inference to dropped spike events due to timeout communication constraints in network connectivity, while maximizing time-to-decision bandwidth and hence minimizing inference energy in the neuromorphic hardware. Simulations with 5-layer fully connected 784-500-500-500-10 SNN on the MNIST task show a 3.42-fold and 7.06-fold decrease in inference energy at 90% test accuracy, by using Dropout and DropConnect respectively during backpropagation training. Also the simulation with convolutional neural networks on the CIFAR-10 task show a 1.24-fold decrease in inference energy at 60% test accuracy by using Dropout during backpropagation training.

The Ul’ya flora comes from the Amka Formation of the Ul’ya Depression, located in the Okhotsk–Chukotka volcanic belt (North-East Russia). This flora includes ~50 species, among which conifers predominate. Ferns and angiosperms are also diverse. The Ul’ya flora is characterized by high endemism and by the presence of numerous Early Cretaceous relicts (Hausmannia, Podozamites, Phoenicopsis, Baiera, Sphenobaiera). Four new endemic species of conifers from the Ul’ya flora are described: Elatocladus amkensis Golovneva, sp. nov., Araucarites sheikashoviae Golovneva, sp. nov., Elatocladus gyrbykensis Golovneva, sp. nov. and Pagiophyllum umitbaevii Golovneva, sp. nov. Two-lobed leaves of Sphenobaiera are assigned to S. biloba Prynada based on their epidermal structure. Because of its systematic composition the Ul’ya flora is correlated with the Coniacian Chaun flora of Central Chukotka, with the Coniacian Aliki flora from the Viliga–Tumany interfluve area, and with the Coniacian Kholchan flora of the Magadan Region. The U-Pb age of zircon (ID-TIMS method) from plant-bearing tuffites within the Amka Formation at the Uenma River is 86.1 ± 0.3 Ma. Thus, Coniacian age (most likely the end of the Coniacian, near the Coniacian/Santonian boundary) is assigned to the Ul’ya flora and plant-bearing pyroclastic deposits of the Amka Formation on the basis of paleobotanical and isotopic data.

Approaches to assessing professional risk are considered for the example of a EuroChem facility. Deficiencies in the program for professional risk assessment outlined in Russian Handbook 2.2.1766–03 are analyzed. This program takes no account of the worker’s age, experience, and overall health. Likewise, statistical data regarding workplace injuries and morbidity are ignored. At the same time, the method of calculating the individual professional risk proposed by the Klin Institute of Labor Protection and Working Conditions permits calculation of the risk for 66 workers and determination of an integral index of professional risk within the organization. Comparison of risk assessments by method in Handbook 2.2.1766–03 and the Klin method shows that the class of working conditions affects the individual professional risk but is not the determining factor.

In this paper, we present the experimental results of complex studies of the sensitivity to mechanical effects and detonation parameters of metalized explosive compositions based on weakly phlegmatized HMX and RDX. Powders of titanium, zirconium, and their hydrides and deuterides were used as fillers. The introduction of these components in an amount of up to 20 wt % is established to contribute to some increase in fire hazard and sensitivity of the compositions in handling them. Estimates show that an increase in the detonation parameters of the mixtures observed in some cases may be due to the chemical reactions of the additives with explosion products in the detonation wave front.

An algorithm is proposed for determining the target development scenario for an industrial emergency arising from terrorist attack or other unsanctioned actions, by assessment of the threats to critical system elements. Criteria are selected for ranking possible scenarios. The target scenario is identified by multicriterial optimization—specifically, by means of the displaced ideal in fuzzy decision making. By means of the algorithm developed for fuel and power companies, a hazard class may be assigned to any unsanctioned intervention, and improved security measures may be developed.

We report on the assembly process and reliability test development of a flexible, biocompatible optoelectronic neural stimulator for a retinal prosthesis. The design and development process for the flexible circuit are discussed. The successful bonding process between six silicon dielets and flexible substrates is presented. The characterization and accelerated lifetime testing are also detailed. The integration techniques described herein may be used to scale up the existing electrode array or for next generation higher visual acuity retinal prostheses. In addition, the methods and setup for lifetime testing may be used in the development of other optoelectronic flexible neural interfaces.

Inductive wireless power transfer empowers microelectronic systems to be implanted in spatially constrained anatomic areas. Due to the need to deliver therapeutic or diagnostic function to sensitive areas, such as the eye, batteries become impractical for reasons of thermal and mechanical safety. In this paper we discuss the requirements and optimization techniques to power an intraocular implant through an inductive coil in the surface of the eye, particularly in the case of a retinal prosthesis. We design and characterize transmitting and receiving inductive coils. Subsequently, through the use of a custom 3D printed mechanical test frame, we characterize the power transfer efficiency at the appropriate geometric parameters. Furthermore, the effect of misalignment, axial displacement, and rotation due to eye movements on power transfer efficiency are quantified in air and through a fragment of animal tissue. These results can be used to model and mitigate movement related power fluctuations.

Recent approaches toward a functional retinal prosthesis to restore vision in neurodegenerative patients have been limited by the number of pixels that can be individually stimulated. The conventional approach, shown in Fig. 18.1.1 (left), uses an external camera to capture video, whose information is then wirelessly delivered to a hermetic housing (typically a titanium can) for conversion to N distinct stimulation pulses fed transocularly to an $N -$ channel microelectrode array (MEA) placed epi- or subretinally. While this approach has proven long-term biocompatibility, translation to 1000s of channels with hermetic and durable transocular connections is not achievable with current technology, limiting existing designs to at most 256 channels, barely sufficient for 20/400 vision restoration [1] –[3]. Instead, recent work has suggested a full-CMOS solution, where an image sensor, stimulation circuits, and an MEA are integrated directly onto a single CMOS chip, thereby eliminating the interconnect challenge and providing a pathway to scalability [4], [5] (Fig. 18.1.1, middle). However, co-location of photoreceptors, amplifiers, and stimulation circuits imposes difficult fill-factor issues, while also significantly increasing heat dissipation near sensitive ocular and neural tissue due to the need to perform voltage regulation, amplification, and charge-balanced stimulation waveform generation (typical end-to-end efficiency of $\sim20$%) right next to the retina. Most importantly, since the CMOS chip must also include electrodes and yet be sufficiently thin to fit epi- or sub-retinally, current encapsulation methods rely on thin-film deposition to enable patterned electrode windows, which has unproven long-term hemiticity or biocompatibility when encapsulating CMOS which has known biological toxins (e.g., copper), limiting practical implementation.