bluuebunny/crossref_metadata_2025 huggingface dataset:
Purification of water from heavy metal ions by a dynamic membrane with a surface layer of cellulose acetate
Authors: Fazullin D D , Fazylova R D
Published: January 2020

To reduce the concentration of heavy metal ions in drinking, natural and wastewater to the established standards, a dynamic membrane with a surface layer of cellulose acetate particles on a nylon substrate was obtained. A dynamic membrane layer was formed from cellulose acetate particles with sizes from 42 to 130 nm. The cellulose acetate content was 14 % by weight, upon receipt from a 10 % solution of cellulose acetate in acetone. After applying a layer of cellulose acetate to the surface of a nylon substrate, a decrease in the specific productivity of the membranes is observed more than 10 times due to the formation of a dynamic layer on the surface and in the pores of the substrate. During the operation of the membrane for 1 hour, there is a decrease in the specific productivity of the membrane by 1.5 times and an increase in the working pressure from 0.35 to 0.41 MPa by 1.2 times. A high selectivity of the dynamic nylon-ACd membrane with respect to iron ions 96%, copper 93% and chromium 93% was established with a specific productivity of 300 dm3/m2·h and a pressure of 0.4 MPa. After purification of tap water with a dynamic membrane, the concentration of heavy metal ions does not exceed the MPC for water bodies for drinking water.
Landscape-hydrological features of the territory of the Kologrivsky Forest Nature Reserve, Russia
Authors: Lebedev A V , Gemonov A V , Azarov G A , Gichan D V , Gostev V V , Druzhininskaya K A , Zmievskaya T V , Kalmykova E S
Published: January 2020

The rivers of the Kologrivsky Forest Nature Reserve are characterized by a pronounced spring flood, summer and autumn low water, which is interrupted by floods and winter low water. Depth, width and flow rate can vary both seasonally and over a short period. At the Kologriv part, there are all the most common low-protocol objects, which are significantly affected by the zoogenic factor of beaver activity. The rivers of the Manturovo part of the reserve significantly differ from the rivers of the Kologriv part both in hydrological and morphological indicators.
Zoning of the territory on the basis of morphometric analysis of basin geosystems
Authors: Erunova M G , Yakubailik O E
Published: January 2020

The problem of creating a geographic spatial database of morphometric indicators based on the basin approach for several rivers in the Krasnoyarsk region is considered. The division of the territory into catchment basins is carried out in a hierarchical system, up to the river tributaries of the 4-th order. The initial data for the construction of watersheds was a MERIT DEM Hydro digital relief model, vector data on the hydrographic network from A.P. Karpinsky All-Russian Research Geological Institute (VSEGEI) and Roscartography (Federal Agency of Geodesy and Cartography). In the process of data processing methods and algorithms of spatial analysis of relief and hydrological modeling, implemented in GIS software Whitebox GAT, QGIS and ArcGIS, were used. The main morphometric characteristics of the relief are calculated: slope, exposure of slopes; with the help of zone statistics for basins, the average values of these characteristics, the main statistics are calculated. We consider this work as the first stage in the creation of information support for the tasks of land use analysis, assessment of the natural resource potential of the region.
Heavy metals accumulation in vegetable crop grown on typical chernozem soils
Authors: Litsukov S D , Akinchin A V , Linkov S A , Shiryaev A V , Kuznetsova L N
Published: January 2020

The article presents agrochemical techniques that reduce the accumulation of heavy metals in vegetable crops, such as potatoes and table beets, when they are cultivated on typical chernozem soils with a heavy loam granulometric composition. The data obtained allowed to conclude that the use of lime, as well as the simultaneous use of lime and manure, reduce the penetration of cadmium in potato tubers by 22 and 18%, respectively. In addition, the use of organic in its pure form reduces the penetration of this element by 8%. The studied cultures absorbed copper, lead and zinc in amounts not exceeding the threshold limit value (TLV), also in plots artificially contaminated with these metals. Heavy metals are more intensely absorbed by the aerial part of potato. During the experiments, it was found that the use of lime, organics, as well as their simultaneous application contributed to a decrease in the studied elements penetration into table beet plants. The increase in the dose of mineral fertilizers doubled positive effect of lower penetration of copper and lead into plants, although the difference was within the experimental error. A double dose of mineral fertilizer did not have any positive effect on the penetration of cadmium and zinc.
Biosorbents for oil-containing wastewater treatment
Authors: Kolotova O V , Mogilevskaya I V , Vladimtseva I V , Arzamasova T D , Kuznetsova V A
Published: January 2020

Investigated data about the selection of the effective microorganisms – oil destructors from the environmental objects and industrial waste. Founded the most active bacterial strains were isolated from the Caspian Sea bottom sediments. Hydrophobicity’s index and emulsifying activity of the most active oil bacterial destructors were defined. Their efficient use of oil or diesel fuel as the only carbon’s source was shown. The growth dynamics of these strains on nutrient containing oil media was studied. Shown the bacterial strain VGTU-02 possessed the greatest speed of growth and destructive activity concerning oil hydrocarbons. Studied the possibility of the using some crop waste and carbonizate from spent activated sludge as a matrix for biosorbents. The microbial base for these biosorbents was the bacterial strain VGTU-02. Selected microorganisms were attached to the studied carriers from the crop waste and waste activated sludge. Efficiency of purification of model liquid from crude oil at use of the suspended VGTU-02 microorganisms with matrixes was defined. Shown that under similar conditions, the highest efficiency of oil purification was achieved 99.41 % for a matrix based on sunflower husk and 98.46% based on carbonizate. The developed biosorbents can be used to remove oil and petroleum products from wastewater.
Mathematical modeling of multilayer road surfaces
Authors: Mikishanina E A
Published: January 2020

The paper is devoted to the mathematical study of elastic states and deformations of multilayer road surfaces under the force of water. The filtration coefficient in the multilayer strip is piecewise constant. Young’s modulus and Poisson’s ratio are given in each band. The problem is reduced to a planar boundary value problem for a system of partial differential equations. A method of constructing solutions to this problem in the form of almost-periodic Bohr functions is investigated. A computational experiment was carried out. Graphs of the required mechanical parameters are constructed, their convergence to the boundary values is shown. The Maple software package was used to build the solutions. The constructed algorithm can be used in solving problems in continuum mechanics.
Features of theoretical models of hardening of piston aluminum alloys in aqueous electrolytes
Authors: Skryabin M L
Published: January 2020

Currently, an effective method of increasing the surface strength and heat resistance of the piston bottom is the method of electrical deposition of chemical coatings based on various compositions. The article deals with the theoretical aspects of the formation of oxide films on piston aluminum alloys during microarc oxidation. Possible schemes of formation of barrier and outer layers of surface coating in aqueous electrolytes are also considered. The mechanism of formation of the interface and possible schemes of deposition of nonmetallic inclusions on the surface are shown. The stepwise formation of oxide layers on the piston surface, which has a fundamental difference from conventional films obtained by anodizing, is described.
Investigation of filter materials for gas cleaning from sulfuric acid
Authors: Tsareva O V , Balyberdin A S , Vakhitov M R , Kharkov V V , Dubkova N Z
Published: January 2020

In the production of sulfuric acid, the final step is to clean the exhaust gases from the sulfuric acid mist. Currently, many industrial enterprises have abandoned the use of electrostatic precipitators to catch acid droplets in favor of the use of bag filters. The authors conducted an experimental study of the effectiveness of various filter materials and their combination in the form of a bag for catching sulfuric acid fog. A filter package was proposed from layers of fiberglass and fluoroplastic materials for industrial use, which showed a 98% efficiency for cleaning exhaust gases from a sulfuric acid mist.
Variability of summer apple tree varieties in 2019 by indicators of vegetative organs
Authors: Bratilova N P , Gerasimova O A
Published: January 2020

The article presents the results of a study of annual shoots of large-fruited apple varieties, characterized by early ripening and consumer maturity, in the Botanical Garden named after Vs. M. Krutovsky. The leaf area, weight of 1 cm2 of leaf and 1 running centimeter of shoot in absolutely dry state are calculated. A significant positive correlation was revealed between the indicators of the area of the sheet and the mass of 1 cm2 of sheet in absolutely dry state, and between the mass of 1 linear cm shoot and 1 cm2 leaf. Using the regression method, it is possible to reduce labor costs for determining phytomass without resorting to additional measurements of the supply of dry foliage mass and to determine the increase in the mass of branches even in leafless periods. In Siberia, it is recommended to use the most promising varieties of apple trees in terms of photosynthetic activity and productivity for cultivation.
Substantiation of vitamin and mineral composition stability of Rubus saxátilis L. berries
Authors: Rygalova E A , Smol’nikova Ya V , Velichko N A , Tarnopol’skaya V V , Mashanov A A
Published: January 2020

For the purpose of continuous research and development of technology for Siberian plant raw material processing as well as obtaining finished products with increased nutritional and biological value, both mineral and vitamin composition of stone brumble berries (Rúbus saxátilis L.) growing in Krasnoyarsk Territory and harvested in various years, were studied. The stone brumble berries were found to be rich in magnesium, calcium, potassium, phosphorus and in vitamins P and C. The analysis of the mineral and vitamin composition of stone brumble berries (Rúbus saxátilis L.) of various years of harvest proved the raw material studied to be a promising stable source of vitamins, macro- and micronutrients. Thus stone brumble berries (Rúbus saxátilis L.) can be recommended as a source of valuable biologically active substances in food production.
The role of the Federal Customs Service in the conservation of Siberian biodiversity
Authors: Zaychenko E A , Petrenko E V , Polyanskaya V V , Parshikova V N
Published: January 2020

The article is devoted to the problem of biodiversity conservation. The law enforcement activity of the Federal Customs Service of Russia to curb illegal trafficking of objects of wild flora and fauna in the Siberian region has been considered. Key areas of cooperation between the customs authorities and the Convention on the International Trade in Endangered Species of Wild Fauna and Flora administration have been identified
Findings of animal and plant objects listed in the Red Book of the Russian Federation on the territory of Shihan Kushtau (Republic of Bashkortostan, Russia)
Authors: Krivosheev M M , Ishbirdin A R , Gerasimov S V , Akhmedyanov D I , Ishmuratova M M , Bykov K S
Published: January 2020

The article presents information about the findings of rare species of plants and animals on the territory of Mount Kushtau (Republic of Bashkortostan). During the period from 2014 to 2019, six representatives of the flora of the species and eight representatives of the fauna listed in the Red Book of Russia were discovered. Their brief characteristics and population characters are given. Based on that studies we recommend that Shihan Kushtau be given the status of a specially protected area.
The influence of diet on the biological activity of the soil and the productivity of grain crops in the Prebaikalia
Authors: Novak S O , Ryabinina O V , Matveeva N V , Boyarkin E V
Published: January 2020

This article presents data on the general effect of foliar top dressing on the yield of cereals such as wheat, triticale, barley and oats on various backgrounds of mineral nutrition. The data on the biological activity of soils by the method of application analysis are also presented. The analysis of weather and agrochemical parameters of the soil, such as the amount of humus, the reaction of the soil solution, and the supply of nutrients that activate the activity of microorganisms and have a significant effect on the productivity of crops. During the research it was found that during the growing season, weather conditions and backgrounds of mineral nutrition had a significant impact on the rate of decomposition of linen. In addition, the influence of various species characteristics of crops on biological activity was noted. In the year of research, the logical effect of extra-root dressing on the studied cultures was not established. The maximum yield increase from the application of foliar top dressing was obtained on a variant of the experiment without the use of fertilizers.
Influence of coniferous-wormwood extract on the viability of bee colonies in Eastern Siberia
Authors: Yudakhina M A
Published: January 2020

The article is devoted to the problems of maintaining viability and increasing the productivity of honey bees in Eastern Siberia. The benefits of coniferous wormwood extract for autumn-spring feeding of bee colonies are described. The researches have shown that bees more actively took food with coniferous wormwood extract than regular sugar syrup. Feeding bees with syrup with extract positively influenced the course of wintering of bees: in the experimental group there was 100% safety. A positive effect of the extract on the development of bee colonies, flight activity of bees was noted: it was seen that the individuals were strong and active. As a result of the researches, it was noticed that after a six-fold feeding of bees with coniferous wormwood extract, the strength of the bee colonies, the average honey and wax productivity, the number of brood and received nucleus increased. The daily increase of population made it possible to maintain an optimal microclimate in the brood nest. It was found that stimulative feeding with the extract increased resistance to such common diseases as varroatosis (there was an 82.8% reduction in the mite strike of bee colonies), nosematosis and ascospherosis. These observations indicate that bee colonies had a huge army of working bees, the microclimate inside the nest was healthy, and it made the maximum use of forces for further increase of individuals and making products.
History of floristic studies in Abakan
Authors: Antipova E M , Chebotareva O P
Published: January 2020

Abakan is a capital of the subject of the Russian Federation, the Republic of Khakassia. The aim of the paper is to identify the history of botanical research on the territory of Abakan in the XX-XXI centuries. The floristic studies were carried out by advanced botanists, scientists of educational institutions (Tomsk State University, Krasnoyarsk State Pedagogical University named after V.P. Astafyev, Khakass State University named after N.F. Katanov) and scientific institutions of Siberia (Central Siberian Botanical Garden of SB RAS, etc.). The historical information collected from publications, route information provided by flora researchers, herbar labels, field diaries and herbarium reports is arranged in chronological order. The early history of the vegetation cover study of Krasnoyarsk Territory and Khakassia (from 1627 to 1954) is described in detail in the work of L.M. Cherepnina, further it is described in the works of N.N. Tupitsyna and others. In the XXI century the floristic studies were continued by representatives of the three scientific schools. The Tomsk school (TSU) is presented by A.L. Ebel, A.I. Pyak and others, the Novosibirsk school (TSSBS SB RAS) is presented by D.N. Shaulo and others and the Krasnoyarsk school (KSPU named after V.P. Astafiev) is presented by E.M. Antipova, T.M. Zorkina, O.P. Chebotareva. This school has a leading role in a special study of the Abakan flora.
Inheritance of hair color in sables (Martes zibellina) of breed black sable
Authors: Beketov S V , Karpov K S , Kozlov A V , Glebova I A , Lopatkov I V
Published: January 2020

On the example of a single population of sables of the Pushkin animal farm (Federal state unitary enterprise “Russkiy Sobol”), the heritability of the general coloring of their hairline was studied. In total, puppies of 1,561 female sables of the black sable breed were analyzed with a total score of 4,794 puppies. Based on the results of the study of various color forms of sables, the heritability coefficients (h2) of the black-brown color form were determined as 0.128; dark brown as 0.108 and chestnut as 0.078, which indicates a high selective sampling for darkening the overall color of the hairline in this population.
Epidemiological survey of ringworm outbreak in cat shelter
Authors: Ovchinnikov R S , Savinov V A , Gaynullina A A , Kapustin A V , Laishevtsev A I
Published: January 2020

Dermatophytosis (ringworm) is the most important infectious and contagious skin disease of cats in shelters. Wherein, the diagnosis, identification and treatment of dermatophytosis is not always effective. Here we report an epidemiological study of the outbreak of feline dermatophytosis in animal shelter in Moscow region. At least 11% of cats kept in the shelter were affected. Seventeen cats suspected dermatophytosis were isolated for mycological examination and treatment, 82% of them were culture-positive. These cats received a course of oral terbinafine, with no topical treatment. Of the dermatophyte-positive cats, 36% demonstrated skin lesions, while 64% were asymptomatic. No mycological control of recovery was carried out after treatment. It was found that 44% of clinically recovered cats turned to be asymptomatic carriers. When examining environmental objects (bedding, cat houses, floors, etc.), dermatophytes were isolated from 80% of the samples. The only causative agent of dermatophytosis was Microsporum canis. The MIC (minimal inhibitory concentration) of terbinafine for clinical strains of M. canis was determined to be 0.001-0.002 μg/ml. The study confirms the need for large-scale mycological screening of cats in shelters using DTM-type diagnostic media. Oral therapy alone is not sufficient for effective treatment; it should include the whole-body antifungal treatment. Mycological control of cure is also mandatory.
Problems of primary seed production of some rice varieties
Authors: Dzhamirze R R , Ostapenko N V , Garkusha S V , Chinchenko N N
Published: January 2020

Rice is a product that combines high calorie content with dietary and medicinal properties. Its consumption in our country, and throughout the world, is constantly growing. In this connection, the relevance of the need to develop new rice varieties that harmoniously combine high yield and excellent grain and milled rice quality is increasing. The key to obtaining quality rice grain and seed is competent seed production work. This article presents the results of many years of research on the possible causes of the appearance of unusual phenotypes (atypical plants) in the primary seed production nurseries of three new rice varieties, fundamentally different in architectonics - Anait (tall, early ripening and large-grain), Sharm (short, early ripening and long-grain) and Lastochka (medium-grown, medium-ripening, medium-grain). Variety Anahit was found to be of different quality according to grain thickness and the weight of 1000 grains. The range of variation in the grain thickness was 1.2– 2.4 mm, and in the weight of 1000 grains - 33.9–44.4 g. Therefore, all plants of this variety were conditionally grouped into two classes and analyzed in detail by family. In the long-grain variety Sharm, an unusual trait appeared - the spinousness of the grain. In the primary seed production nursery in 2016, out of 600 sown plots, 329 plots had different types of spinousness. It is considered that the set of chromosomes according to spinousness trait in the variety Sharm included both recessive and dominant genes (an1, An2⁕, An3⁕; An1⁕, An2⁕, an3). And in the event of an unfavorable combination of circumstances (abiotic and anthropogenic factors) in 2015, in the phase of heading-flowering in the variety during fertilization, gene unlocking occurred, as a result of which atavistic traits started being observed in the progeny. In variety Lastochka, families significantly differed both among themselves and in the years of cultivation, in resistance to blast and in the mass of 1000 grains. In the process of primary seed production during family-wide selection, families with average resistance to blast and with improved technological milled rice characteristics were identified.
ROS-based robot offline planning simulation system
Authors: Liu Zhiheng , Chen Jian , Mei Zhen , Li Chao
Published: January 2020

In order to realize the rapid and automatic generation of robot motion trajectory, a robot offline planning simulation system was developed based on ROS platform. This paper analyzes the model STL file, reconstructs the topology data structure, generates the model minimum bounding box, and obtains the model surface path through the slicing algorithm to generate the processing path. The system loads the Moveit motion planner, applies different motion planning methods, generates a collision-free, continuous motion trajectory, and visualizes the offline planning process. The simulation verification system can realize the functions of rapid path generation on the workpiece surface and obstacle avoidance motion planning of the robot arm. It can realize offline programming of robots and improve the efficiency of robot teaching.
Dynamic Performance Analysis of the micro-hole EDM Machine Tool
Authors: Liu Jian-Yong , Wang Min , Hu Jian-Fei , Qin Peng , Shi Long , Cai Yanhua
Published: January 2020

The EDM machine is special processing machine using the principle of EDM process of conductive materials. By means of modal analysis, ODS (Operational, Deflection, Shapes) analysis and order analysis, the static and dynamic performance parameters of the EDM machine tool are studied. According to the processing requirements, the structure of the machine tool is optimized, and the weak links are strengthened so as to reduce the aperture dispersion of the machined holes. Through the modal test this experiment firstly analyzes the natural frequency, damping ratio and modal shape in each mode of machine tool structure to understanding the characteristics of each order machine main mode. Then, through ODS (Operational Deflection Shapes) test, it analyzes the vibration characteristics of machine tool structure in operation condition. And it also analyzes the relation-shape between the vibration of rotating machinery and the speed of the machine through the order analysis to predict the vibration of actual machine tool structure in a certain band external or internal variety of vibration response. Finally, it makes a comprehensive study on the static and dynamic performance of machine tools, and provides a reference for the design and optimization of structure dynamic strength.
Study on the prediction method of supporting force distribution and experiment
Authors: Ma Hongfeng , Liu Gaojie
Published: January 2020

The supporting force distribution is very important for the vehicle to maintain safety and stability, especially for the heavy-duty refitting vehicle with eccentric load. A simple and generic model to compute the supporting force distribution is essential in the design stage of refitting vehicle, whereas there is little research involving in solving this problem by now. This article presents an efficient and simple method to predict the supporting force of tire (supporting point). Firstly, the model for the vehicle with three or four axles is simplified. The mathematical matrix is established by force equilibrium equation, moment equilibrium equation and deformation compatibility equation. With the known parameters of load, position and dimension, the force of every supporting point can be calculated, and so the supporting force distribution is acquired. Then, a corresponding experiment is designed and implemented. According to the results of the comparison, the results indicate that the general prediction method to calculate supporting force distribution presented in this paper is accurate and validated in the pre-design stage of the refitting vehicle.
Finite Element Analysis of the Maintenance Robot with Charged Used in Substation
Authors: Dong Xu , Li Jianxiang , Li Jian , Chen Qiang , Liu Jizhi , Li Tao
Published: January 2020

The Maintenance Robot with Charged Used in Substation is mainly used for the maintenance tasks with hot-line in 220kV substation. It is mainly composed of the mobile chassis and insulated lifting arm. The end of insulated lifting arm is matched with different working tools to achieve different tasks. The robot needs to maintain the stability of the mechanical body during working, so the dynamic characteristics of the robot cannot be ignored. The finite element structure analysis of the robot body under working conditions is carried out, and the stress distribution and structural deformation diagram of the robot mechanical body under working conditions are obtained in this paper. The qualitative analysis of the material concentration in the stress concentration part is carried out due to the calculation results. The low-order vibration frequency of the robot and the corresponding mode shape are obtained by preload modal analysis. The dynamic characteristics of the robot during the operation are analyzed based on the preload modal analysis results.
Experimental research on explosion resistance of masonry structures reinforced with modified polyurea elastomer
Authors: Tao Xigui , Jia Yifan , Fan Chengfei
Published: January 2020

In order to improve the explosion resistance performance of masonry structures during the terrorist attacks and accidental disasters, clay brick and concrete block walls are reinforced by modified polyurea materials. Explosion resistance tests of these two kinds of masonry wall structures are carried out to analyze the failure modes and anti-explosion effects of reinforced masonry walls under different thickness and reinforcement modes. The results show that modified polyurea elastomer not only has good spraying adhesion and compatibility with the base material surface, but also can effectively encapsulate the explosive debris generated by the back blasting surface of the masonry wall under explosive load, which reduces the deformation and displacement of the wall.
Design of Full Automatic Inspection Robot and Optimized Modification of Overhead Ground Transmission Line
Authors: Cao Lei , Guo Rui , Li Jianxiang , Zhang Feng , Zhou Dazhou , Jia Juan , Lu Shibin
Published: January 2020

In order to achieve the full autonomous inspection of the robot along the overhead ground line, a new type of robot operation mode is proposed by considering the overhead ground line and the robot as a whole. According to the characteristics of obstacles encountered by the robot, the optimization design of the overhead line and the structure design of the robot body are carried out. By transforming the line, a obstacle-free path suitable for the robot was build to pass through, which simplifies the obstacle crossing action and improves the obstacle crossing efficiency.
Cause Analysis and Suggestion on Corrosion Leakage of Pipe in Atmospheric and Vacuum Pressure Unit
Authors: Du Liang , Wang Qingjin , Li Xuan , Yan He
Published: January 2020

An 800,000 tons/year atmospheric and vacuum distillation unit suffered from corrosion and leakage of the atmospheric top volatile pipeline, which resulted in unplanned shutdown, seriously affecting the safe and stable operation of the unit. In this paper, the corrosion mechanism, raw materials, anti-corrosion measures and operation management are analyzed. The causes of corrosion leakage accidents are given and the relevant suggestions for corrosion control and protection are put forward.
Research on the development mode of general exclusive parts for spacecraft integration
Authors: Zou Chen , Zhang Lei , Zheng Jiandong , Zou Shuang
Published: January 2020

As an important part of spacecraft, the research on general exclusive parts for spacecraft integration is still in its infancy. In this paper, based on the characteristic of spacecraft and exclusive parts, the development mode of general exclusive parts and the principles of configuration management for general exclusive parts are established. This paper explores the working mode of general exclusive parts adding, modification, abolition and deviation. Furthermore, this paper also suggests the thoughts on the construction of relevant databases.
Tensile constitutive model of reactive powder concrete based on flexural experiment
Authors: Li Wangwang , Ji Wenyu , Su Yonghua , Ban Xinlin
Published: January 2020

Reactive powder concrete(RPC) is a kind of ultra high performance concrete material, which has ultra high compressive strength and durability as well as good tensile property, elastic modulus, energy absorption and ductility. All these properties make it to be a better choice for the construction of bridges, buildings, military architectures, nuclear structures and the buildings bearing severe environment. The good tensile property, durability and ductility of RPC depend on the steel fibres mixed in the concrete. The bridge effect of steel fibres provides high tensile strength and crack resistant property. The tensile constitutive model of RPC differs from the normal concrete. This study tried to obtain the tensile constitutive model of RPC based on the flexural experiments of RPC prism. On the basis of test results, the tensile constitutive model of RPC is given in this study.
CHAMU: An effective approach for improving the recycling of tea waste
Authors: Gao Pin , Ogata Yoshito
Published: January 2020

With the development of tea production, treating tea waste has become a problem that cannot be ignored. Here, we reprocessed tea waste to create a new kind of biomass material and named it “CHAMU”. We found that tea waste is a good fiber raw material and can improve the degradation rate of PLA composites in the soil. Based on the above findings, we established a tea waste recycling system. During the processing, it was found that tea stems, tea residue had better plasticity than wood-shaving materials. According to this characteristic, we designed a series of “CHAMU products” to explore “CHAMU” materials in product design.
Research on Laser Welding Organization Performance of Fe-Mn-Si Alloy
Authors: Liu Linlin , Dong Huajun , Wang Xiaochi , Zhou Chaoyu
Published: January 2020

The crystal morphology and formation of the microstructure of the laser weld of Fe-Mn-Si memory alloy were analyzed by metallographic microscope and scanning electron microscope(SEM) and X-ray diffractometer (XRD). The results show that the welding seam microstructure of Fe-Mn-Si memory alloy crystallizes symmetrically from the fusion zone on both sides to the weld center. The γ→ε martensite transformation occurs in the welding seam and its adjacent tissues due to laser welding. This is because of the residual stress generated in the welding process, and this kind of ϵ martensite transformation and its deformation relaxes the residual stress of the weld, thus affecting the mechanical properties of the weld.
Protection of magnesium melt by hexafluoropropylene/air atmosphere
Authors: Jiang Hongli , Chen Hukui , Huang Jie , Mu Xiaxia , Jiang Yu , Jie Yangyang
Published: January 2020

The protection of hexafluoropropylene/air mixed gas for molten magnesium at temperatures from 670 °C to 800 °C has been investigated. The morphology and the composition of the protective film formed on the surface of the melt at 700 °C for holding time of 30 min and 60 min were investigated by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The results showed that the protective effect of the mixed gas on molten magnesium increased with the increasing of hexafluoropropylene concentration, the prolongation of holding time and the decrease of temperature. The protective film on the surface of the melt was uniform and continuous, and mainly composed of MgF2 and small amount of MgO.
Modeling and Simulation of Vibrating Online Viscometer System
Authors: Li Pengcheng , Wang Liheng
Published: January 2020

Aiming at the present situation of the difficulties in the analysis and research of the vibration type on-line viscometer system, the structural characteristics and mathematical model of the vibrating online viscometer are analyzed and studied. Based on this, the closed-loop control principle is further elaborated. At the same time, the simulation model of the vibrating online viscometer system was built by closed-loop control technology. The MATLAB simulation results verify the accuracy of the closed-loop control and the effectiveness of the simulation model, which provides a theoretical basis and guiding ideas for the system design and debugging of the vibrating online viscometer.
Implementation Of Medical Pendant Interactive System Based On Virtual Reality Technology
Authors: Li Hanyang , Duan Dini , Zhang Zhisheng
Published: January 2020

Nowadays, virtual reality is in the stage of rapid development. Rational application will improve the immersive feeling of human-computer interaction. This paper discusses the construction of interactive experience learning system from two perspectives of platform interaction experience and user demand. This system can provide the operation and practice platform of medical tower related equipment, and build a realistic medical environment based on Unity3D and HTC Vive. The base station of the equipment realizes the real-time positioning of users through the signals transmitted by the handle, in order to ensure the effectiveness and immersion of user interaction, and providing information such as equipment introduction, operating instructions, precautions and emergency operation tips of the medical tower. In order to improve the learning efficiency of users, the learning progress of users is recorded in real time, the tactile feedback device on the handle is used to prompt users when they make mistakes. This system provides an interactive platform for medical staff and professionals to learn and train medical hanging towers. It is also expected to serve as the basis for further research on virtual reality technology in the medical industry and improve people’s interactive experience in the virtual environment.
Analysis of Weak Point of Fluid Material Tank Based on FLUENT
Authors: Li Yongqiang , He Zhiyuan
Published: January 2020

In view of the high reliability requirements of fluid material tanks and the difficulty of quality inspection, FLUENT is used to construct the tank model as a set of physics variable values on a finite number of discrete points. The original continuous physical field (pressure field and velocity field, etc.) of the fluid in the time system and the space system is replaced by certain laws and principles. At the same time, an algebraic equations are established for the relationship between these finite number of discrete points, and then the basic method of finite element method is used to solve the algebraic equations, and then the relative approximation of the stress acting on the tank in the time and space systems is obtained. After a continuous accelerated simulation, the weak link of the tank is finally determined.
Stress Rupture Properties of Welded Joints of Austenitic Heat-resistant Super304H Steel at 650 °C
Authors: Li Xinmei , Zhang Zhongwen , Du Baoshuai , Suo Shuai , Li Wen
Published: January 2020

With the help of metalloscope, scanning electron microscope and its energy dispersive spectroscopy, this paper investigates the stress rupture properties at high temperature and microstructure changes of the welded joints of austenitic heat-resistant Super304H steel at 650 °C as well as the effects of microstructure changes on stress rupture properties by high temperature creep rupture testing. The results show that at 650 °C, the welded joint of Super304H steel has high breaking strength at elevated temperature, and the fracture position is on the base material away from the fusion line, and the fracture type is mainly a transcrystalline rupture. The microscopic process of creep rupture of Super304H steel welded joints is the nucleation and growth of the void and crack, while the large bulk Nb(C,N) is the main nucleation site of void. As the careep time increases, M23C6 on the grain boundary is also the main nucleation site of the void.
Design and Fabrication of a High Precision Constant Current Source Current Generator
Authors: Li Xiulian
Published: January 2020

A high precision constant current generator with current sources is designed. It adopts precise operational amplifier circuits, high precision constant current sources and FPGA chips. It can generate sine waves, triangle waves and square waves (the duty cycle is adjustable) with adjustable frequency and high precision. The output current ranges from 0 to 4000mA, which can be set as required. It has digital display and strong anti-interference ability, which can provide the current with 0.05% precision. In this paper, the working principle and design idea of the circuit are analyzed. The whole program is compiled under the environment of Lab VIEW, and the assembly, welding and debugging of the circuit are completed.
Experimental Research on Fracture Toughness and Tensile Strength of Red Sandstone under Different Moisture Content
Authors: Li Chunting , Yuan Tingwei
Published: January 2020

In order to study the variation and correlation of mode I fracture toughness and tensile strength of red sandstone under different moisture content conditions, Brazilian splitting and NSCB tests were carried out on the red sandstone specimens with moisture content of 0%, 1.63% and 3.33% respectively by using the CMT53 test loading system, and the test data obtained were fitted and analyzed. The test results show that: 1. The tensile strength and fracture toughness of red sandstone gradually decrease with the increase of moisture content, and the softening effect of water on red sandstone is obvious, with the reduction coefficients of 0.72 and 0.66, respectively. 2. With the increase of moisture content, the dispersion of tensile strength and fracture toughness of red sandstone increases. 3. The fitting formulas of water content and tensile strength and fracture toughness are obtained by data fitting, and the fitting correlation is relatively high. The piecewise function is used to describe the relationship between tensile strength and fracture toughness. It is convenient to estimate the fracture toughness of red sandstone through its tensile strength and it has a certain reference value for studying the relationship between tensile strength and fracture toughness of red sandstone.
Effect of calcium chloride on hydration kinetics and pore structure of hydrated tricalcium silicate
Authors: Li Qinfei , Yang Wang , Chen Heng , Hou Pengkun , Cheng Xin
Published: January 2020

Chemical admixtures are frequently used to regulate the setting and strength development of concrete materials. In this study, tricalcium silicate (C3S) was used as a model of the cement system, and the influence of calcium chloride, an extremely useful accelerator, on C3S hydration and the pore structure of hardened C3S paste were investigated by the combination of the techniques of differential scanning calorimetry (DSC) and the N2 adsorption (BET). The results indicated that the addition of calcium chloride would significantly shorten the pre-induction and induction periods and enhance the specific surface area and porosity of hardened C3S paste. However, the presence of CaCl2 has little effect on the pores, with a width ranging from 2.5 nm to 5 nm. DSC technique has an advantage of measuring continuously the process of C3S hydration by changes of free water in hydrated C3S.
Optimum Design of Transmission Coil for Giant Magnetostrictive Actuator
Authors: Zeng Fan , Shi Feng , Hui Ying
Published: January 2020

The driving coil is optimized by replacing the magnetic field with ampere turns. For a variety of wire diameter, select the appropriate trade-off between the ampere-number maximization and the power minimization when the volume is closest to its allowable value and does not exceed the maximum output current of the power supply. It is calculated that 1mm diameter coil has the minimum power consumption. Therefore, choose 1mm diameter enameled wire to wound coil.
Corrosion behavior of 316L stainless Steel under Cl− corrosion medium
Authors: Xie Jun Jun , Ningyu Heng , Sun Xu , Yang Zhan Jun
Published: January 2020

316L stainless steel is widely used in the fields of thermonuclear industry and petrochemical industry due to its excellent comprehensive mechanical properties and corrosion resistance. Especially in the petroleum industry, 316L stainless steel is commonly used as oil pipelines and storage tanks because of its high corrosion resistance to media such as CO2. However, 316L stainless steel will pitting in a high Cl− concentration environment, posing a potential risk to these devices. At present, there is not enough data to show that whether 316L stainless steel will bring about pitting or stress corrosion cracking under the synergistic effect of high stress and high Cl− concentration, this brings higher risks to the application and promotion of this material. In response to this phenomenon, the paper uses constant stress corrosion cracking method, and analyzes the fracture by scanning electron microscope (SEM). Researching 316L Stainless Steel corrosion behaviors and corrosion creeps in different Cl− concentration solutions.
Thermal Analysis of Double Mass Flywheel Secondary Flywheel
Authors: Yan Zhengfeng , Yin Dale , Zhou Kunpeng , Chen Lei
Published: January 2020

To solve the problem of thermal overload failure in dual-mass flywheel (DMF), we performed temperature field calculation and thermal analysis of the secondary flywheel in DMF. Based on the results of this analysis, we performed thermal stress analysis on the secondary flywheel. The heat transform model was built for the secondary flywheel using the thermodynamics theory. Finite element model (FEM) was built for the secondary flywheel using ABAQUS 6.12-3 software. This model was solved to obtain the distributions of the temperature field and thermal stress in the secondary flywheel after it completed five engagement-disengagement cycles. Finally, thermal shock test was conducted for the secondary flywheel on the thermal shock test bench. We performed a targeted test to verify the accuracy of thermal analysis of secondary flywheel. The analysis method can be used to optimize product parameters such as the product thickness.
Theoretical Analysis of Residual Head Velocity after the Jet Penetrating the Multi-layer Metal-Liquid Composite Structure
Authors: Zhao Changfang , Ren Jie , Kuai Tengfei , Zhou Zhitan , Zhang Kebin , Zu Xudong , Le Guigao
Published: January 2020

The residual head velocity after the jet penetrating a target plate is an indication of the residual penetration capability of the jet, which changes obviously with the penetration time. In this study, the residual head velocity after the jet penetrating through the n-layer metal and the n-layer liquid was deduced by using the quasi-steady penetration model theory. The influence of shock wave to the residual head velocity of jet was analyzed. The calculation results show that the residual head velocity of the jet decreases with the increase of the number of layers of the composite structure, and the shock wave obviously affects the velocity of the residual head of the jet but not very strong. According to the difference between the experimental value and the theoretical value of the jet penetrating the single-layer composite structure, a method of modifying the theoretical mathematical model by using constant C as the calibration value is proposed. The mathematical model can be extended to calculate the residual head velocity of the jet penetrating the multi-layer metal-liquid composite structure with different materials and thickness.
A SEM Study on Space Environment Effects of Carbon Nanotube Arrays
Authors: Tian Dongbo , Liu Yuming , Li Man
Published: January 2020

Due to their unique properties, carbon nanotubes will have great potential applications in many fields, particularly in space applications. But in development of carbon nano-materials intended for operation in aerospace, one of the most important problems is assurance of their resistance against the impact of the AO which is one of the predominant environment in space. Here we present the AO erosion effects on pure carbon nanotube arrays by SEM analysis. It is shown that the morphologies of CNT arrays are quite different from those before AO experiments. Different morphologies of CNT arrays after AO exposure are shown by SEM images. It is presented that shrinkage and crack formation of CNT arrays are caused by bombardment force.
Effect of basalt fiber on chloride ion penetration of Reactive Powder Concrete
Authors: Zhao HaiLong , Wang LuLiang , Wang Dehong , Bai Junfeng , Fan Yunting
Published: January 2020

In order to investigate the influence of the basalt fiber on the durability of reactive powder concrete (RPC), chloride ion penetration test of nine groups of RPC containing basalt fiber and three groups of RPC without fiber was carried out, carbonization test of one group of basalt fiber RPC was performed. The result showed that, the electrical flux of RPC without basalt fiber varied from104-120C, the chloride ion permeability was very low. The electrical flux of basalt fiber RPC was less than 100C, so the chloride ion permeability can be ignored. When water-to-binder ratio (W/B) was 0.22 and volume fraction of basalt fiber was 0.10%, the chloride ion permeation resistance of specimens was the best. The basalt fiber RPC had good carbonization resistance, and the carbonation depth was zero in 28 days.
Experimental Study of Transmission Tower Damage Detection Using Time Series Model
Authors: Guo Huiyong , Wang Zhihua
Published: January 2020

In order to solve damage detection problem of transmission tower, a damage index based on inter-storey stiffness and cepstral distance is presented. First, transmission tower model is established and the tower is divided into six sub-structures. Thus, we only need to identify the sub-structure location where the damaged rods are included. Then, autoregressive model is introduced, the cepstral distance between autoregressive models under damaged and undamaged states is given, and a damage index based on inter-storey stiffness and cepstral distance is proposed. Finally, the experiment of transmission tower model is conducted to evaluate the effectiveness of detecting the damaged layer of transmission tower. The analysis results of the experimental signals show that the damage index based on inter-storey stiffness and cepstral distance is an available method for damage detection of transmission tower, and the damage feature can be well extracted with the damage index.