bluuebunny/crossref_metadata_2025 huggingface dataset:
Probing heat generation during tensile plastic deformation of a bulk metallic glass at cryogenic temperature
Authors: Brennhaugen David D. E. , Georgarakis Konstantinos , Yokoyama Yoshihiko , Nakayama Koji S. , Arnberg Lars , Aune Ragnhild E.
Published: October 2018

Despite significant research efforts, the deformation and failure mechanisms of metallic glasses remain not well understood. In the absence of periodic structure, these materials typically deform in highly localized, thin shear bands at ambient and low temperatures. This process usually leads to an abrupt fracture, hindering their wider use in structural applications. The dynamics and temperature effects on the formation and operation of those shear bands have been the focus of long-standing debate. Here, we use a new experimental approach based on localized boiling of liquid nitrogen by the heat generated in the shear bands to monitor the tensile plastic deformation of a bulk metallic glass submerged in a cryogenic bath. With the “nitrogen bubbles heat sensor”, we could capture the heat dissipation along the primary shear banding plane and follow the dynamics of the shear band operation. The observation of nitrogen boiling on the surface of the deforming metallic glass gives direct evidence of temperature increase in the shear bands, even at cryogenic temperatures. An acceleration in bubble nucleation towards the end of the apparent plastic deformation suggests a change from steady-state to runaway shear and premonitions the fracture, allowing us to resolve the sequence of deformation and failure events.
Fabrication of highly effective hybrid biofuel cell based on integral colloidal platinum and bilirubin oxidase on gold support
Authors: Hasan Md Qumrul , Kuis Robinson , Narayanan J. Shankara , Slaughter Gymama
Published: October 2018

A hybrid biofuel cell (HBFC) is explored as a low-cost alternative to abiotic and enzymatic biofuel cells. Here the HBFC provides an enzymeless approach for the fabrication of the anodic electrode while employing an enzymatic approach for the fabrication of the cathodic electrode to develop energy harvesting platform to power bioelectronic devices. The anode employed 250 μm braided gold wire modified with colloidal platinum (Au-co-Pt) and bilirubin oxidase (BODx) modified gold coated Buckypaper (BP-Au-BODx) cathode. The functionalization of the gold coated multi-walled carbon nanotube (MWCNT) structures of the BP electrodes is achieved by 3-mercaptopropionic acid surface modification to possess negatively charged carboxylic groups and subsequently followed by EDC/Sulfo-NHS (1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-Hydroxysulfosuccinimide) crosslinking with BODx. The integration of the BODx and gold coated MWCNTs is evaluated for bioelectrocatalytic activity. The Au-co-Pt and BP-Au-BODx exhibited excellent electrocatalytic activity towards glucose oxidation with a linear dynamic range up to 20 mM glucose and molecular oxygen reduction, respectively. The HBFC demonstrated excellent performance with the largest open circuit voltages of 0.735 V and power density of 46.31 μW/cm2 in 3 mM glucose. In addition, the HBFC operating on 3 mM glucose exhibited excellent uninterrupted operational stability while continuously powering a small electronic device. These results provide great opportunities for implementing this simple but efficient HBFC to harvest the biochemical energy of target fuel(s) in diverse medical and environmental applications.
Conserved Pbp1/Ataxin-2 regulates retrotransposon activity and connects polyglutamine expansion-driven protein aggregation to lifespan-controlling rDNA repeats
Authors: Ostrowski Lauren A. , Hall Amanda C. , Szafranski Kirk J. , Oshidari Roxanne , Abraham Karan J. , Chan Janet N. Y. , Krustev Christian , Zhang Kevin , Wang Ashley , Liu Yupeng , Guo Ru , Mekhail Karim
Published: October 2018

Ribosomal DNA (rDNA) repeat instability and protein aggregation are thought to be two major and independent drivers of cellular aging. Pbp1, the yeast ortholog of human ATXN2, maintains rDNA repeat stability and lifespan via suppression of RNA–DNA hybrids. ATXN2 polyglutamine expansion drives neurodegeneration causing spinocerebellar ataxia type 2 and promoting amyotrophic lateral sclerosis. Here, molecular characterization of Pbp1 revealed that its knockout or subjection to disease-modeling polyQ expansion represses Ty1 (Transposons of Yeast) retrotransposons by respectively promoting Trf4-depedendent RNA turnover and Ty1 Gag protein aggregation. This aggregation, but not its impact on retrotransposition, compromises rDNA repeat stability and shortens lifespan by hyper-activating Trf4-dependent turnover of intergenic ncRNA within the repeats. We uncover a function for the conserved Pbp1/ATXN2 proteins in the promotion of retrotransposition, create and describe powerful yeast genetic models of ATXN2-linked neurodegenerative diseases, and connect the major aging mechanisms of rDNA instability and protein aggregation.
Methylome of human skeletal muscle after acute & chronic resistance exercise training, detraining & retraining
Authors: Seaborne R. A. , Strauss J. , Cocks M. , Shepherd S. , O’Brien T. D. , Someren K. A. van , Bell P. G. , Murgatroyd C. , Morton J. P. , Stewart C. E. , Mein C. A. , Sharples A. P.
Published: October 2018

DNA methylation is an important epigenetic modification that can regulate gene expression following environmental encounters without changes to the genetic code. Using Infinium MethylationEPIC BeadChip Arrays (850,000 CpG sites) we analysed for the first time, DNA isolated from untrained human skeletal muscle biopsies (vastus lateralis) at baseline (rest) and immediately following an acute (single) bout of resistance exercise. In the same participants, we also analysed the methylome following a period of muscle growth (hypertrophy) evoked via chronic (repeated bouts-3 sessions/wk) resistance exercise (RE) (training) over 7-weeks, followed by complete exercise cessation for 7-weeks returning muscle back to baseline levels (detraining), and finally followed by a subsequent 7-week period of RE-induced hypertrophy (retraining). These valuable methylome data sets described in the present manuscript and deposited in an open-access repository can now be shared and re-used to enable the identification of epigenetically regulated genes/networks that are modified after acute anabolic stimuli and hypertrophy, and further investigate the phenomenon of epigenetic memory in skeletal muscle.
Datasets from a research project examining the role of politics in social psychological research
Authors: Viganola Domenico , Eitan Orly , Inbar Yoel , Dreber Anna , Johannesson Magnus , Pfeiffer Thomas , Thau Stefan , Uhlmann Eric Luis
Published: October 2018

We present four datasets from a project examining the role of politics in social psychological research. These include thousands of independent raters who coded scientific abstracts for political relevance and for whether conservatives or liberals were treated as targets of explanation and characterized in a negative light. Further included are predictions about the empirical results by scientists participating in a forecasting survey, and coded publication outcomes for unpublished research projects varying in political overtones. Future researchers can leverage this corpus to test further hypotheses regarding political values and scientific research, perceptions of political bias, publication histories, and forecasting accuracy.
Computational Materials Discovery: Dream or Reality?
Authors: Oganov Artem R. , Kvashnin Alexander G. , Saleh Gabriele
Published: October 2018

Without new materials there would be no new technologies, just old bottlenecks. Until a few years ago, new materials could only be discovered experimentally. Now the situation is dramatically different: having solved the crystal structure prediction problem—the most formidable obstacle on the way to computational materials discovery—computational design of materials has become a reality. This ongoing scientific revolution has already led to the prediction of new materials with superior properties, with subsequent experimental confirmation.
Computational Materials Discovery Using Evolutionary Algorithms
Authors: Oganov Artem R. , Kruglov Ivan , Zhang Jin , Davari Esfahani M. Mahdi
Published: October 2018

Evolutionary algorithms, as implemented in the USPEX code, offer a very attractive and powerful way for computational materials discovery, and this is demonstrated by their very wide applications. In this chapter we review this methodology, its adaptation to variable-composition systems, surfaces, nanoparticles, molecular crystals, and proteins. We discuss the reasons why it works so well. We discuss a number of interesting applications of this methodology to materials discovery—including superhard materials, high-Tc superconductors, high energy density materials, electrides, 2D-materials, polymers, and chemically anomalous solids and nanoparticles.
Applications of Machine Learning for Representing Interatomic Interactions
Authors: Shapeev Alexander V.
Published: October 2018

Machine learning focuses on prediction, based on known properties learned from training data. In computational materials science, this powerful technique is often used for constructing new interatomic potentials. These approaches are illustrated in this chapter, and the improvements over the empirical force fields are discussed.
Chemical Bonding Investigations for Materials
Authors: Saleh Gabriele , Ceresoli Davide , Macetti Giovanni , Gatti Carlo
Published: October 2018

The technologically relevant properties of materials and their electronic structure are intimately connected, but such a connection is by no means intuitive. Chemists rationalize the electronic structure of compounds through the analysis of their chemical bonding network, that is through the construction of a set of paradigms that aim at predict and explain the properties of materials. This chapter gives a broad overview of the most widely adopted chemical bonding investigation tools. For each of them, we review the theory behind its underpinning paradigms and illustrate some representative applications. The last section of the chapter is devoted to discussing the synergic use of chemical bonding tools in compounds with non-conventional bonding patterns as well as in technologically-relevant materials.
First-Principles Computational Approaches to Superconducting Transition Temperatures: Phonon-Mediated Mechanism and Beyond
Authors: Akashi Ryosuke
Published: October 2018

The long-sought goal of materials science, the computational discovery of new superconductors, is now becoming possible thanks to recent advances in the first-principles computational methods to calculate the superconducting transition temperature (Tc. We review the theoretical background of such methods, as well as their modern numerical implementations and applications to existing and theoretically predicted materials.
Rationalising and Predicting the Structure and Bonding of Bare and Ligated Transition Metal Clusters and Nanoparticles
Authors: Frapper Gilles , Halet Jean-François
Published: October 2018

During the last 50 years, experimental chemists have forged thousands of molecular ligated transition metal clusters and particles with an enormous variety of complicated and/or unexpected structures and compositions. Theoretical models and rules have greatly assisted these developments by explaining the stability and shape of the clusters and particles. However, research is now extending towards the investigation of larger ligated or bare species at (or approaching) the nanoscale, where electron-counting rules and models mainly based on the closed-shell principle can lose their relevance and are often replaced (or accompanied) by increasingly powerful computational tools. We examine these qualitative and quantitative computational tools from a historical perspective and with a view to their future application in the theoretical and experimental study of bare and molecular ligated transition metal clusters and particles. Case studies are discussed to illustrate how computational rationalisation and, to a lesser extent, prediction of large transition metal cluster and particle structures has developed into a sophisticated and successful field of research.
Discovery of Novel Topological Materials Via High-throughput Computational Search
Authors: Autès Gabriel , Yazyev Oleg V.
Published: October 2018

Topological materials realize new states of matter characterized by the topologically non-trivial electronic structure. Since the discovery of topological insulators, their study has been fruitful for both the theoretical and the experimental side of condensed matter physics. First-principles electronic structure calculations have played a key role in the rapid development of the field by facilitating the identification of materials realizing new topological phases envisioned by theorists. Following this success, we implement a high-throughput computational search scheme to uncover novel topological materials, thus providing a new playground for the fundamental study of topological phases and their potential technological applications.
Computational Discovery of Organic LED Materials
Authors: Gómez-Bombarelli Rafael , Aspuru-Guzik Alán
Published: October 2018

Automation, software and machine learning are enabling a data-driven revolution in areas such as self-driving cars, logistics, manufacturing and finance. In this chapter, we describe how these tools are being combined for computer-driven discovery of thermally activated delayed fluorescence materials. We analyze the increasingly automated deployment of robust and accurate computer simulations to assess candidate molecules virtually and identify leads for experimental characterization. Recent advances in machine learning techniques to accelerate the screening process and to increase its accuracy are also described. The role of user-experience and custom experiment–theory interaction tools are described. Finally, we report how these computer-based efforts have resulted in novel high organic light-emitting diode materials.
Photoelectrochemical CO2 reduction to adjustable syngas on grain-boundary-mediated a-Si/TiO2/Au photocathodes with low onset potentials
Authors: Li Chengcheng , Wang Tuo , Liu Bin , Chen Mengxin , Li Ang , Zhang Gong , Du Minyong , Wang Hui , Liu Shengzhong Frank , Gong Jinlong
Published: October 2018

This communication describes collaboration between a grain-boundary-mediated Au catalytic layer and a TiO2-protected a-Si absorber towards adjustable PEC syngas production with low onset potentials.
Structure–activity relationship of the cinnamamide family of antibiotic potentiators for methicillin-resistant Staphylococcus aureus (MRSA)
Authors: Speri Enrico , Fishovitz Jennifer , Mobashery Shahriar
Published: October 2018

MIC of oxacillin against S. aureus (MRSA252 strain) reduced from 256 μg mL−1 to 2 μg mL−1.
Combining electronic and structural features in machine learning models to predict organic solar cells properties
Authors: Padula Daniele , Simpson Jack D. , Troisi Alessandro
Published: October 2018

Combining electronic and structural similarity between organic donors in kernel based machine learning methods allows to predict photovoltaic efficiencies reliably.
Carbon-encapsulated multi-phase nanocomposite of W2C@WC1−xas a highly active and stable electrocatalyst for hydrogen generation
Authors: Kim Inha , Park Sung-Woo , Kim Dong-Wan
Published: October 2018

A new strategy for the synthesis of carbon-encapsulated tungsten carbide nanoparticles is demonstrated for highly stable electrocatalysis for hydrogen evolution.
Helicity control of π-conjugated foldamers containing d-glucose-based single enantiomeric units as a chiral source
Authors: Ikai Tomoyuki , Minami Serena , Awata Seiya , Shimizu Sho , Yoshida Takumu , Okubo Mitsuhiro , Shinohara Ken-ichi
Published: October 2018

We have succeeded in the helicity control of polymer backbones and their circularly polarized luminescence without the need for chirality of an unnatural antipode, l-glucose.
Total synthesis of μ-conotoxin lt5d
Authors: Naraga A. M. B. , Belleza O. J. V. , Villaraza A. J. L.
Published: October 2018

The total synthesis of μ-conotoxin lt5d is presented for the first time employing two different strategies.
Simultaneous improvement in electrical conductivity and Seebeck coefficient of PEDOT:PSS by N2pressure-induced nitric acid treatment
Authors: Zar Myint May Thu , Hada Masaki , Inoue Hirotaka , Marui Tatsuki , Nishikawa Takeshi , Nishina Yuta , Ichimura Susumu , Umeno Masayoshi , Ko Kyaw Aung Ko , Hayashi Yasuhiko
Published: October 2018

As a thermoelectric (TE) material suited to applications for recycling waste-heat into electricity through the Seebeck effect, poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonic acid) (PEDOT:PSS) is of great interest.
Computational investigation of the control of the thermodynamics and microkinetics of the reductive amination reaction by solvent coordination and a co-catalyst
Authors: Boz Esra , Tüzün Nurcan Ş. , Stein Matthias
Published: October 2018

Green production of tertiary amine from sustainable sources can be controlled by appropriate choice of reaction parameters identified by computational means.
Bimetallic nickel–cobalt hydrides in H2 activation and catalytic proton reduction
Authors: Chu Xiaoxiao , Jin Jihao , Ming Bangrong , Pang Maofu , Yu Xin , Tung Chen-Ho , Wang Wenguang
Published: October 2018

The synergism of the redox properties of nickel and cobalt enables bimetallic NiCo complexes to process H2.
Palladium-scavenging self-assembled hybrid hydrogels – reusable highly-active green catalysts for Suzuki–Miyaura cross-coupling reactions
Authors: Slavík Petr , Kurka Dustin W. , Smith David K.
Published: October 2018

From waste to wealth – a self-assembled hydrogel remediates palladium from solution down to sub-ppm levels, and the resulting gel, which has embedded Pd nanoparticles, acts as a green and efficient catalyst for Suzuki–Miyaura cross-coupling reactions.
Alkali–oxygen treatment prior to the mechanical pulping of hardwood enhances enzymatic hydrolysis and carbohydrate recovery through selective lignin modification
Authors: Wu Jie , Chandra Richard , Saddler Jack
Published: October 2018

A “one-pot” approach using alkaline-oxygen modified lignin, maximized carbohydrate recovery and increased hydrolysis yields of mechanical pulp more effectively than a pre-hydrolysis approach.
Excimer emission induced intra-system self-absorption enhancement – a novel strategy to realize high efficiency and excellent stability ternary organic solar cells processed in green solvents
Authors: Du Xiaoyang , Liu Bin , Li Lijuan , Kong Xiao , Zheng Caijun , Lin Hui , Tong Qingxiao , Tao Silu , Zhang Xiaohong
Published: October 2018

A novel ternary OSC with enhanced PCE and environmental stability has been obtained via utilizing excimer enhanced energy transfer.
Multi-component non-fullerene acceptors with tunable bandgap structures for efficient organic solar cells
Authors: Gao Bowei , Yao Huifeng , Hou Junxian , Yu Runnan , Hong Ling , Xu Ye , Hou Jianhui
Published: October 2018

Six-component OSCs are fabricated by selecting one donor and five non-fullerene acceptors, exhibiting easily tuned current and voltage.
Recent progress in live cell mRNA/microRNA imaging probes based on smart and versatile nanomaterials
Authors: He Dinggeng , Wong Ka-Wang , Dong Zhenzhen , Li Hung-Wing
Published: October 2018

We summarize the recent progress in live cell mRNA/miRNA imaging probes based on various versatile nanomaterials, describing their structures and their working principles of bio-imaging applications.
How to measure test repeatability when stability and constant variance are not observed
Authors: Jing Gary G.
Published: October 2018

Passive intermodulation (PIM) is a critical measurement for radio frequency (RF) communication networks. Yet PIM measurement inherently has very poor repeatability, which makes product assessment unreliable. The RF industry struggles with the issue since there are no known solutions. With the increasing demand for low-PIM performance, there are pressing demands to address the challenge. Two fundamental problems make traditional gage R&R study invalid for PIM: (1) PIM in nature is unstable and unrepeatable; (2) PIM measurement has inherently inconstant variance at different PIM levels, which is primarily due to limited capability of PIM analyzer. This resulted in several less-known issues significantly impacting the estimation of PIM test repeatability, including sample selection, one-sided spec and differences between test R&R and gage R&R. The paper proposed two fundamental changes when studying R&R of PIM test or tests in general violating constant variance assumptions: (1) sample selection; (2) what measurement to use to better estimate and represent the test repeatability. Special sampling is proposed to minimize the impact of inconstant variance. A more direct R&R measurement, margin of error (MOE), also known as study variation, is proposed to replace traditional gage R&R metrics to more meaningfully represent PIM test R&R. Several statistically based techniques to improve the repeatability and reliability of PIM measurement are also discussed. The study and proposed solutions apply to not only PIM test but also tests in general violating constant variance assumptions.
Design and technological methods of reducing of thermal stress in grinding process
Authors: Ivanova Tatyana N.
Published: October 2018

When grinding wheel comes in contact with machined surface thermal coupling occurs between the detail, shavings and cooling lubrication fluid. Depending on machining conditions, heat passes into detail machined from 50 to 83% which results in steel defects. Using results of carried research of thermal fields, thermal processes in grinding operations may be controlled. Through these processes we control quality of upper layer. As the result of carried research the next data are obtained: functional dependence, which allows calculating of rate of heating and cooling for every part of detail to be machined according to machining mode, time and intensity of heating source; dependence of stress calculation on operating time and temperature of heating source while grinding process is carried
The process of interaction between abrasive disk and a workpiece while grinding under ultrasonic vibrations
Authors: Unyanin Alexandr , Khazov Alexandr
Published: October 2018

This research includes the analysis of kinematic relations between abrasive disk grains and the workpiece in the abrading process while applying ultrasonic vibrations (USV) on the workpiece. Supposition, that applying vibrations lied in axes of abrasive disk increases efficiency of disk grinding, has been set. Analytical approach showed dependences for calculating the grinding force. These dependences include changing of disk grains microcutting kinematics and mechanical characteristics of workpieces while applying USV. The technique of pilot studies is given. For imposing on preparation of USV used the device in which it was one of links of oscillatory system that provides the minimum losses of energy USV and high amplitude of fluctuations of preparation. Field researches have shown, that applying USV lied in axes of abrasive disk decreased the grinding force, the wear of disk, and high-level parameters of the processed surface roughness.
Application of two-component technological media for surface processing with a high degree of curvature
Authors: Smolentsev Vladislav , Kuzovkin Alexej , Drozdov Igor
Published: October 2018

The final dimensional combined treatment with the application of an electric field by a tool in the form of unbound metal pellets of complex profile components used in aviation, rocket and space technology and in the oil and gas industry is considered. Such parts include impellers and the flowing component of the turbo-pump units, augers, impellers, where there are sections of variable curvature with limited access of the tool to the processing area. It is shown that the combination in a combined process of two-component technological media from current-carrying granules and an electrically conductive liquid medium supplied at high speed to the treatment zone allows to provide the required technological and operational processing parameters; the action of an electric field from a source with an increased voltage makes it possible to remotely perform a final dimensional processing of the pieces of metal parts with the creation of the required coldhardening against the impacts of solid granules; a combination of mechanical, chemical and magnetic impacts ensures obtaining a given profile accuracy, surface roughness. As a result, it is possible to increase the action and durability of important units of aerospace engineering and oil and gas equipment, and also to expand the area of technological use of the combined treatment method with unbound granules to component parts that are not accessible for processing by an integral tool. In the method under consideration, a universal granule tool is used which does not have a constant geometric shape and is capable of being delivered to the treatment zone through openings into parts whose dimensions are commensurable with the cross-section of the granules.
Chemical polishing of samples obtained by selective laser melting from titanium alloy Ti6Al4V
Authors: Balyakin Andrey V. , Shvetcov Aleksei N. , Zhuchenko Evgeny I.
Published: October 2018

The paper discusses a method of chemical polishing of Ti6Al4V samples and presents the results of our study. The samples were produced by selective laser melting, which is an increasingly popular method of producing thin-walled, geometrically complex products. The document analyzes how polishing with solutions featuring a varying content of hydrofluoric and nitric acids affects the etching rate and alters the superficial roughness of the samples in both the longitudinal and the transverse directions. We have thus formulated the recommendations on the optimum composition and concentration of such acidic solutions for polishing Ti6Al4V products made by selective laser melting.
Fundamental research and methods of quality assurance of coated abrasive
Authors: Syreyshchikova Nelli V. , Pimenov Danil Yu.
Published: October 2018

The article presents the results of the development of scientific and methodological provisions of quality assurance of a coated abrasive (CA) based on the formation of the sets of indicators: technological, performance (existing and newly introduced), reflecting its physical and mechanical properties and economic, which allowed us to classify and evaluate the CA according to their purpose, use it economically and efficiently based on the developed CA design recommendations.
Theoretical investigation of the effect of the taper angle of the deforming roller on the limiting degrees of deformation in the process of flow forming
Authors: Udalov Andrey A. , Parshin Sergey V. , Udalov Aleksandr V.
Published: October 2018

The conditions for the application of taper angles of deforming rollers are considered in the article, which ensure a steady flow of the flow forming. With the help of the developed engineering technique, analytical and graphical dependences of the boundary values of the deformation degrees on the cone angle of the deforming roller are obtained. The results of the theoretical study are in good agreement with the known experimental data. The developed engineering technique can be used in designing the flow forming on the direct and reverse method, as well as for any process of pressure treatment with a local focus of deformation.
Achieving high quality surface of laminated glass-reinforced plastics during milling
Authors: Rychkov Daniel , Lobanov Dmitry , Kuznetsov Aleksey
Published: October 2018

Milling is one of the most common ways of workpiece machining, but obtaining a high quality surface of laminated composite materials is difficult due to their layered structure, high strength characteristics and low heat conductivity. This poses a problem of creating a milling technology that provides a high quality surface. This research investigates STEF -1 glass-fiber plastic with fine grain structure processed on the equipment with high cutting speed. The object of the research is roughness Ra as a quality criterion. Our glass-fiber plastic milling experiments demonstrate that the surface quality depends to a large extent on the cutting modes and the wear level of the tool cutting edge which is determined by the size of the wear bevel on the flank surface. The blade of the cutting tool is established to wear unevenly during glass-fiber plastic processing as it interacts with two different materials. We recommend the wear bevel on the flank surface to be less than 0.35 mm to ensure the high quality of the laminated composite material surface. The cutting modes should be within the following range: feed per tooth is 0.15 ÷ 0.17 mm/tooth, cutting depth is 0.5 ÷ 0.9 mm, cutting speed is above 45 m/s, with the cutting part of the tool being made of high-strength instrumental materials.
Vibratory drilling with digital adaptive control
Authors: Ivanov Ilya , Pleshcheev Ivan , Larkin Andrey
Published: October 2018

High standards and efficiency of deep hole drilling used for hard-to-machine metals and alloys could not be achieved if chips are not segmented in the cutting zone. Chip control could be achieved through transmission of harmonic vibrations to the drill in direction of its rotating axis. One way to maintain these vibrations is to replace a drill chuck with a special self-vibratory drilling head, which includes an elastic element that allows axial movement of the tool. The right stiffness value of an elastic element and appropriate machining conditions could lead to oscillation self-excitation of a drill due to the regenerative mechanism. It is advisable to support this mechanism with a control action defined within the feedback loop, which provides process quality necessary for chip control in the broad range of process parameters. This work analyzes adaptive control algorithm for vibratory drilling process dynamics where control action over an oscillating system is proportional to drill axial vibrational velocity, and a feedback gain is determined in the adaptation loop. Dynamics modeling of a closed-loop nonlinear system “elastic system-machining process-control system” is carried out for cases with or without control proving effectiveness of control algorithm. The model was used to analyze how control system analog-to-digital conversion parameters influence vibratory process quality. Requirements, which ensure control system achieves a control aim, were approximately stated for capacity and response limit for analog-to-digital conversion.
Determination of machining errors caused by dynamic deformations from process equipment
Authors: Starikov Aleksandr , Putilova Ulyana , Tempel Olga
Published: October 2018

A method for determining and inputting the correction value is presented based on the data obtained as a result of the diagnosis of a CNC milling machine during machining curvilinear surfaces.
Methodology of designing integrated technological processes for manufacturing CNC machined parts
Authors: Guzeev Viktor I. , Pimenov Danil Yu.
Published: October 2018

The article presents a new approach to the design of technological processes of processing parts on metal cutting machines in the integrated production conditions based on the expected forecast of the parts processing accuracy. The stages of choosing the parameters of processing steps are combined with determining the parameters of the cutting tool and machining attachments by simulation modeling. The design sequence begins with the first operation.
Efficiency improvement for assigning of cutting conditions on the basis of the thermo-EMF signal
Authors: Tikhonova Zhanna , Kraiynev Dmitriy , Frolov Evgeniy
Published: October 2018

In the realities of modern machine-building production, control and management of processes occurring in the cutting zone are of great importance. The acquisition of control will significantly improve the stability and quality of processing, and the possibility of monitoring will help to increase the economic efficiency of production. This article presents the potential of the thermo-emf signal in a natural thermocouple “tool – workpiece” which is considered to be an information signal from the cutting zone. It also shows experimental proof of the influence between honing width on the front surface of the tool and its size.
Investigation of cutting force oscillations when high productivity milling
Authors: Aleynikov Dmitry , Lukyanov Anatoly , Savilov Andrey , Paikin Dmitry
Published: October 2018

The article analyzes cutting force oscillations of high-productivity milling. Based on end-milling experiments using a milling machine tool, characteristics of spatial oscillations of cutting forces were identified. The data analysis using software and oscillation theory methods showed that at high spindle rotation frequencies under certain milling conditions, interaction of the cutting edges and the workpiece is not uniform which deteriorates the machined surface. As the spindle rotation frequency increases due to resonances in the tool and spindle and mutual oscillations of the workpiece and the tool, the cutting force spectrum varies. Some extra harmonic components appear. They index the failure of interaction of the cutting edges and the workpiece.
Features of technological basing in machining parts on CNC machines
Authors: Nosov Nicolay V. , Cherepashkov Andrey A.
Published: October 2018

The article discusses the problems of computer aided design and technological preparation of production of complex shape parts on machines with numerical program control. An integrated technique for designing processes and control programs for CNC machines is proposed and described, using the technique of software-based referencing and modern electronic measuring tools.
Design of an expert system for the prediction and comprehensive diagnosis of CNC machining fault
Authors: Al-Jonid Khalid , Kozlov Alexander , Baryshev Nikolay
Published: October 2018

Unlike the earlier research works which only focused on fault diagnosis, in this paper a smart fault preventive step is taken in avoiding some category of failures which may be predicted at the initial stage of CNC operation before a fault is diagnosed. Besides this, the domain of fault diagnosis has also been expanded by incorporating human error which was not part of the earlier system. This is the first phase of the study and a comprehensive fault diagnosis expert system algorithm for CNC machine is going to be designed, which can later on be transformed into a knowledge-based intelligent computer applications program. This will be accomplished by consulting experts on various aspects of CNC operations.
Processing of parts for aerospace engineering
Authors: Boldyrev Alexander I. , Boldyrev Alexander A. , Fedonin Oleg N.
Published: October 2018

The article is devoted to combined processing techniques applied in modern industrial production for fabrication of aerospace engineering parts. The attainable process parameters are found for each technique. It is shown that electrochemical mechanical processing technique has maximal technological capability, this allows the increase of endurance strength and decrease of item mass.
Development of an algorithm for calculating the number of regrindings for a shaver with the continuous spiral cutting edge
Authors: Golovko Aleksandr
Published: October 2018

There is a construction of tool of a worm type (shaver) at that a cutting wedge has the structurally performed clearance. In this case is possibility of the sequential processing of right and left side of profile of gear teeth of wheel different spiral cutting edges. It provides the increase of firmness of tool, diminishes auxiliary time, except the necessity of refixturing of wheel and promotes the productivity of process. For the effective use of shaver with spiral cutting edges it is important to define the exact meaning of amount of possible regrinds. An algorithm that allows to define the amount of possible regrinds of shaver is presented in the article.
Enhance the efficiency of the internal threads cutting process with taps by applying ultrasonic vibrations
Authors: Golovkin Valery , Batishcheva Oksana , Papshev Valery
Published: October 2018

The paper considers a technological process of an advanced method of cutting internal threads using ultrasonic vibrations. A special ultrasonic device is shown, which makes it possible to realize this method of ultrasonic processing. The paper also presents research findings of ultrasonic vibrations influence on the process of cutting internal threads.
The relation between the geometric parameters of grinding powders grains measured by laser diffraction and light-microscopical methods
Authors: Nosenko Vladimir A. , Aleksandrov Alexey A.
Published: October 2018

The studies were conducted on grinding powders of black silicon carbide with F180-F60 grit produced by Volzhsky Abrasive Plant. The length, width, perimeter, area and reduced diameter of the grain area were determined by light-microscopical method, the equivalent diameter by the laser diffraction method. The distribution laws of geometric parameters are determined. A direct proportional relationship between the mean equivalent diameter and the average geometric parameters of the grain fractions (length, width, perimeter, equivalent diameter) and the power-law dependence with the average area of the grain fractions have been established
Interrelation of processing modes with the current parameters of the contact zone during thermofriction processing
Authors: Pokintelitsa Nikolay
Published: October 2018

The establishment of the interrelation between the processing modes and the current parameters of the contact zone during the thermofriction processing of flat surfaces of workpieces by a rotating disk tool is considered. Dependencies are presented allowing assignment of cutting modes, prediction of the size of the removed material layer, and determination of the control actions value.
Evaluation of the influence of manufacturing errors on the quality of sealing joints installation
Authors: Tarakhovskiy Aleksey , Kramar Vadim
Published: October 2018

In production process, the leading role belongs to installation as a final stage, where the main quality indicators, reliability and durability of the produced objects are formed. However, the analysis of machine building development trends in the recent years shows that even in such highly automated industries as automobile and tractor construction, in view of labor intensity, installation takes second place after machining. In the general structure of labor intensity of machine manufacture, it amounts to 35-60% of the total labor intensity and exceeds labor costs at all stages of production [1]. In machine building, about 25-30% of operations are mechanized, and no more than 5-6% of operations are automated [1]. Therefore, installation works are inefficient and expensive, resulting in the significant increase of the finished product cost and decrease of its quality.
The study of algorithms for 3D’s engineering object representing with regard to their construction specifics
Authors: Sokolova Ekaterina
Published: October 2018

This work deals with algorithms of 3D object representation with due regard to their construction specifics. The criterion of the integral adjacency of an unambiguous/fuzzy truth value to the absolute truth value is analyzed.
The performance evaluation for rivet bonded joints in production and machine maintenance
Authors: Baurova Natalia , Anoprienko Alexander , Romanova Yulia
Published: October 2018

The paper deals with the studies on the serviceability and performance of rivet bonded joints produced with the use of thermoplastic hot-melt adhesives. Thermoplastic hot-melt adhesives are compared with conventional epoxy adhesives. The performance evaluation of different adhesive materials by dismantling of rivet bonded joints is fulfilled. The time necessary for each operation of the process is considered. The algorithms are provided for finding the design and engineering solution when replacing the conventional process of riveting by rivet bonding in production and machine maintenance.
Method for constructing an equivalent mechanical model of an elastic system of a machine with various technological equipment
Authors: Vasilevykh Sergey L. , Udalov Alexandr V. , Shelihov Evgeniy S.
Published: October 2018

The article deals with the construction of an equivalent mechanical model of the elastic system of the machine for turning non-rigid shafts with various technological equipment, including machining in centers and machining in a chuck with the rear rotating center being clamped without using additional support and using a vibration-damper lunette. The relevance of this study due to the fact that in view of low stiffness processed non-rigid shaft technology system machine-tool-tool-workpiece is extremely sensitive to the deformations caused by the action of cutting forces. As a result, significant processing errors are generated. High sensitivity to deformations serves as a source of intensive vibrations of the workpiece, which leads to deterioration of the quality of the machined surface of the part, a decrease in the durability and durability of the cutting tool, accelerated wear and loss of guaranteed machine accuracy parameters. This makes it essential to significantly reduce the cutting conditions, to resort to multi-pass processing, which greatly increases the laboriousness and cost of manufacturing products. In this context, the aim of this study – the creation of an equivalent mechanical model of the machine, allowing the process of studies to determine the boundaries of sustainable non-rigid turning shafts considering the different ways of mounting the workpiece on the machine. The materials of the article can be useful for engineers and scientists in the field of engineering.
Analytical testing and methods for increasing the durability of plunger hydraulic cylinders
Authors: Antsupov Aleksandr , Antsupov Viktor , Slobodianskii Mikhail
Published: October 2018

The article deals with the important problem of increasing the operating life of roll-balance system plunger hydraulic cylinders and describes the solution to this problem. The durability of plunger hydraulic cylinders determines not only the overall reliability of a hydraulic system, but also the technical and economic efficiency of the whole wide-strip hot rolling mill. Hydraulic cylinder durability depends primarily on the wear resistance of sealing units. Therefore in order to provide an effective approach to increasing the hydraulic cylinder life we have developed an analytical method for determining wear resistance of sealing units (i.e. determining a class or category) and calculating their expected operating life. The method is based on the solution of the fundamental equation of energy and mechanical theory of stationary units wear-fatigue as well as the theoretical provisions describing the strain pattern, initial and limiting values pertaining to plunger cylinders sealing units operating conditions. We have performed a computer experiment to study the behavior of various sealing materials and plungers with different antifriction coatings. As the result of the experiment we have established a number of ways to improve wear resistance of sealing units and durability of hydraulic cylinders by utilizing more durable elastomers and application of double-layer metal-polymer coatings. The most reliable design options of sealing units have been pilot tested and put into operation.
Finite element method application to calculate the friction discs of the hydromechanical transmission control system
Authors: Khomichev Alexey , Trusevich Ilya
Published: October 2018

In article presents the results of experimental researches of friction elements of a hydromechanical transmission control system, the loadings to which they are subjected. Substantiates the need to improve the methodology for calculating friction discs.
Ensuring the amphibious capabilities of the amphibious vehicle based on the hydrodynamic buoyancy principle
Authors: Abdulov Sergei , Trusevich Ilya , Volkov Alexander
Published: October 2018

This work substantiates the technical solutions for ensuring high water speed of the future amphibious vehicle by the implementation of the movement regime based on the principle of hydrodynamic buoyancy. The conclusions obtained in the course of the search work are proved with the help of computational hydrodynamics modeling.
Bending strength assessment of chemically-heat-strengthened Novikov gearing
Authors: Beskopylny Alexey , Onishkov Nikolay , Korotkin Victor
Published: October 2018

The article is devoted to the refinement of the flexural strength assessment of surface-strengthened gears with Novikov’s engagement. For standard involute wheels the results that were calculated in accordance with existing regulations and experiments could differ by an order of magnitude, or even more, then for Novikov’s transmissions, only partial recommendations based on experiments are relatively reliable. The influence of several factors, such as the possible initiation of flexural fractures under the action of contact stresses on the tooth’s leg, as well as the peculiarities of cyclic loading of gear teeth with two lines of engagement, have not been studied in practice. The purpose of this article is to assess the influence of tensile stresses on the boundary of the instantaneous contact spot in the conditions of reducing the plastic properties of the material due to thermal (chemical-thermal) treatment. The presence of a dangerous cross-section on the border of the active and transitional sections of the tooth profile is presented, which may not coincide with the area of action of the maximum tensile stresses, in which two essentially different types of stress-strain state will alternate, which considerably complicates the assessment of accumulation of fatigue damages.
The modeling of an anthropomorphic robot arm
Authors: Kabanov Aleksey , Balabanov Aleksey
Published: October 2018

This paper considers the anthropomorphic manipulator kinematics modeling problem. The considered anthropomorphic robot SAR-400 manipulator with five-fingered gripper has twelve degrees of freedom. In the paper the robot SAR-400 arm kinematic model and the simulation results are presented.
Features of designing hydraulic excavator in APM WinMachine
Authors: Shestakov Viktor , Babenkov Pavel , Horoshavin Sergey
Published: October 2018

The urgency of the work is due to the need for design departments involved in the design of hydraulic excavators in techniques. Allowing to reduce the weight of excavators while providing at the same time sufficient reliability. The purpose of the work: development of a technique for application in the design of excavators of calculation modules based on the use of finite elements. Research methodology: modeling of working equipment. For a hydraulic excavator with a “direct” shovel working equipment, a mathematical model for calculating effort, an algorithm and a program in an algorithmic language have been developed, which allow to determine the working area of the excavator, possible digging forces, and efforts in the elements of the working equipment. To calculate stresses in the design of the working equipment, two modeling options are proposed: the models for the Strucrure 3D computational module are compiled separately for the bucket of the handle and the boom, the interaction of the models is carried out by efforts that are determined by the specified digging forces; a complete model of all the working equipment for the calculation module is compiled, without the need to calculate the loads between the elements, the calculation is carried out directly by the digging force. For the first variant formulas of calculation of efforts in elements of the working equipment are resulted. For the second variant, it is suggested to use a plate-rod model, and recommendations are given for the implementation of the relationships between the boom, the handle and the bucket. The results of stress calculations for the working equipment are presented.