scholarly journals Influence of hard alloys CEDG modes on the size of dissolved layer

2018 ◽  
Vol 224 ◽  
pp. 03002
Author(s):  
Olga Medvedeva ◽  
Pavel Arkhipov ◽  
Alexander Yanyushkin
Keyword(s):  
Removal Rate ◽  
Machine Building ◽  
Grinding Wheel ◽  
Anode Current Density ◽  
Hard Alloys ◽  
Processed Material ◽  
Quantitative Characteristics ◽  
Modes Of Processing ◽  
Mechanical Cutting ◽  
Qualitative And Quantitative Characteristics

Correctly assigned technological modes of processing define the accuracy of forming, optimum mechanical and electrochemical speed of the processed material removal, quality and durability of the cutting tool as well as provide the self-sharpening conditions for the grinding wheel. The purpose of this work is to increase the efficiency of hard alloys combined electric diamond grinding (CEDG) by establishing a dependence between the amount of material removed by mechanical cutting and the depth of the layer dissolved by electrolytic processes. Achieving the stated goal allows to solve the problem of defects occurrence on the processed surface and to minimize economic expenses for machine-building production processing. The article presents the results of mathematical calculations of the parameters influence on the size of the dissolved surface layer, as well as the current dependent removal rate for hard alloys. We determine qualitative and quantitative characteristics of the hard alloy dissolved layer dependence on the mechanical and electrical parameters of CEDG, such as the depth of grinding and anode current density, and demonstrate their analytical dependence.

A Study on Grinding Tungsten Carbide with Ultrasonic Assisted

2013 ◽  
Vol 797 ◽  
pp. 374-381
Author(s):  
Pei Lum Tso ◽  
Chao Chun Tseng
Keyword(s):  
Tungsten Carbide ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Cutting Temperature ◽  
Limited Range ◽  
Machining Process ◽  
Grinding Wheel ◽  
Hard Alloys ◽  
Ultrasonic Assisted

In order to cope with high demanded industry requirements. The super-hard alloys such as Tungsten Carbide have been widely used in aerospace and defense industries. So far, the grinding operation is still the most popular machining process being used to cut these materials in shape. But, owing to the nature of these materials mechanical properties, always made it very difficult to grind as well as to cut. Nevertheless, the allowable grinding parameters are resisted to very limited range and always require use very expensive super abrasive grinding wheel. Recently, study by many researchers show that the ultrasonic assist grinding had the advantage of higher material removal rate, less cutting force and lower cutting temperature. In the mean time, the tool life had been improved greatly. In this study, the conventional GC grinding wheel was used in the experiments to study the material removal rate; grinding force; surface roughness as well as specific grinding energy with and without the ultrasonic assist. The results show that these difficult-to-cut materials can be ground easier with proper ultrasonic assist and low-priced grinding wheel.

Assessment of drugs increasing the reproductive function of cows of oocyte donors

2020 ◽  
pp. 122-126
Author(s):  
A. Plakhova ◽  
K. Plemyashov
Keyword(s):  
Maximum Concentration ◽  
Ultrasound Examination ◽  
Reproductive Function ◽  
Experimental Animals ◽  
Qualitative And Quantitative ◽  
Quantitative Characteristics ◽  
Oocyte Donors ◽  
Experimental Group ◽  
Qualitative And Quantitative Characteristics ◽  
Donor Cows

In these studies, a comprehensive assessment of the effect of the drugs «Carofertin» and «Hemobalance» on the reproductive function of oocyte donor cows was carried out. At the same time, the effect of these drugs on the biochemical parameters of blood serum, as well as on the concentration of progesterone, carotene in the experimental groups and the activity of the ovaries in the experimental animals was assessed. An increase in the activity of alkaline phosphatase in the first and third experimental groups was found, which amounted to 128.80 and 104.6 IU / L. There was also a decrease in the concentration of cholesterol in the experimental groups compared with the control. The maximum concentration of carotene was noted in the experimental group No. 1, which were injected with «Carofertin» subcutaneously, and in the experimental group No. 3, which were injected with «Carofertin» and «Hemobalance». The maximum concentration of progesterone was also noted in groups No. 3 and No. 1 and amounted to 21.98±3.03 and 17.01±9.68 nmol / l, respectively. In the course of ultrasound examination of the ovaries in experimental animals, a relationship was noted between the concentration of progesterone and the intensity of the blood supply of the corpus luteum on the ovaries in experimental animals. Subsequently, in one animal from each experimental group, oocytes were aspirated (OPU) twice with an interval of two weeks and their qualitative and quantitative characteristics were assessed. The maximum number of oocytes suitable for use was noted in the experimental group No. 3, which was injected with both study drugs.

Formation of work models ormation of work models of nursing staff of different levels

2020 ◽  
pp. 39-47
Author(s):  
Irina Muntyan
Keyword(s):  
Nursing Staff ◽  
Nursing Personnel ◽  
Methodological Basis ◽  
Qualitative And Quantitative ◽  
Quantitative Characteristics ◽  
Work Model ◽  
Different Levels ◽  
Qualitative And Quantitative Characteristics

The work model of a nurse includes 14 elements representing the qualitative and quantitative characteristics of the work. The analysis of these elements allowed us to form and offer work models for senior and rankand-file nurses. These models ensure selection, evaluation and placement of nursing personnel on a uniform methodological basis.

Quantitative and Qualitative Characteristics of Urban Discharge to Small River Basins in the South West of Sweden

1983 ◽  
Vol 14 (3) ◽  
pp. 155-166 ◽  
Author(s):  
Wm. Hogland ◽  
R. Berndtsson
Keyword(s):  
River Basins ◽  
Small River ◽  
The South ◽  
Time Intervals ◽  
Qualitative And Quantitative ◽  
South West ◽  
Quantitative Characteristics ◽  
Qualitative Characteristics ◽  
Qualitative And Quantitative Characteristics

The paper deals with the qualitative and quantitative characteristics of urban discharge. Ratios for urban discharge and recipient flow during different time intervals are presented and discussed. The quality of the urban discharge is illustrated through pollutographs.

Fractional Dynamic Sliding Mode Control for uncertain chaotic systems Applied to a Chaotic Robot arm under dynamic load.

2020 ◽  
Vol 10 ◽  
Author(s):  
Sara Gholipour P ◽  
Sara Minagar ◽  
Javad Kazemitabar ◽  
Mobin Alizadeh
Keyword(s):  
Sliding Mode Control ◽  
Chaotic Systems ◽  
Control Method ◽  
Sliding Mode ◽  
Qualitative And Quantitative ◽  
Mode Control ◽  
Quantitative Characteristics ◽  
Dynamic Sliding Mode Control ◽  
Dynamic Sliding Mode ◽  
Qualitative And Quantitative Characteristics

Background: A novel type of control strategy is presented for control of chaotic systems particularly a chaotic robot in joint and workspace which is the result of applying fractional calculus to dynamic sliding mode control. Objectives: To guarantee the sliding mode condition, control law is introduced based on the Lyapunov stability theory. Methods: A control scheme is proposed for reducing the chattering problem in finite time tracking and robust in presence of system matched disturbances. Conclusion: Also, all of chaotic robot's qualitative and quantitative characteristics have been investigated. Numerical simulations indicate viability of our control method. Results: Qualitative and quantitative characteristics of the chaotic robot are all proven to be viable thru simulations.

scholarly journals Study on the Effect of Grinding Pressure on Material Removal Behavior Performed on a Self-Designed Passive Grinding Simulator

2021 ◽  
Vol 11 (9) ◽  
pp. 4128
Author(s):  
Peng-Zhan Liu ◽  
Wen-Jun Zou ◽  
Jin Peng ◽  
Xu-Dong Song ◽  
Fu-Ren Xiao
Keyword(s):  
Residual Stress ◽  
Surface Roughness ◽  
Service Life ◽  
Material Removal ◽  
Removal Rate ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Temperature ◽  
Grinding Efficiency

Passive grinding is a new rail grinding strategy. In this work, the influence of grinding pressure on the removal behaviors of rail material in passive grinding was investigated by using a self-designed passive grinding simulator. Meanwhile, the surface morphology of the rail and grinding wheel were observed, and the grinding force and temperature were measured during the experiment. Results show that the increase of grinding pressure leads to the rise of rail removal rate, i.e., grinding efficiency, surface roughness, residual stress, grinding force and grinding temperature. Inversely, the enhancement of grinding pressure and grinding force will reduce the grinding ratio, which indicates that service life of grinding wheel decreases. The debris presents dissimilar morphology under different grinding pressure, which reflects the distinction in grinding process. Therefore, for rail passive grinding, the appropriate grinding pressure should be selected to balance the grinding quality and the use of grinding wheel.

Development of a New Plate Polishing Technique with an Instantaneous Tiny-Grinding Wheel Cluster Based on Magnetorheological Effect

2008 ◽  
Vol 53-54 ◽  
pp. 155-160 ◽  
Author(s):  
Qiu Sheng Yan ◽  
Ai Jun Tang ◽  
Jia Bin Lu ◽  
Wei Qiang Gao
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Grinding Wheel ◽  
Abrasive Particles ◽  
Magnetorheological Effect ◽  
Material Removal Model ◽  
Mr Effect ◽  
Removal Model

A new plate polishing technique with an instantaneous tiny-grinding wheel cluster based on the magnetorheological (MR) effect is presented in this paper, and some experiments were conducted to prove its effectiveness and applicability. Under certain experimental condition, the material removal rate was improved by a factor of 20.84% as compared with the conventional polishing methods with dissociative abrasive particles, while the surface roughness of the workpiece was not obviously increased. Furthermore, the composite of the MR fluid was optimized to obtain the best polishing performance. On the basis of the experimental results, the material removal model of the new plate polishing technique was presented.

Parametric Study of Micro Machining Three Dimensional Microstructure with the Tiny-Grinding Wheel Based on the EMR Effect

2010 ◽  
Vol 447-448 ◽  
pp. 193-197
Author(s):  
Wei Qiang Gao ◽  
Qiu Sheng Yan ◽  
Yi Liu ◽  
Jia Bin Lu ◽  
Ling Ye Kong
Keyword(s):  
Magnetic Field ◽  
Material Removal Rate ◽  
Feed Rate ◽  
Material Removal ◽  
Rotation Speed ◽  
Optical Glass ◽  
Removal Rate ◽  
Grinding Wheel ◽  
Machining Time ◽  
Fluctuation Phenomenon

Electro-magneto-rheological (EMR) fluids, which exhibit Newtonian behavior in the absence of a magnetic field, are abruptly transformed within milliseconds into a Bingham plastic under an applied magnetic field, called the EMR effect. Based on this effect, the particle-dispersed EMR fluid is used as a special instantaneous bond to cohere abrasive particles and magnetic particles together so as to form a dynamical, flexible tiny-grinding wheel to machine micro-groove on the surface of optical glass. Experiments were conducted to reveal the effects of process parameters, such as the feed rate of the horizontal worktable, feeding of the Z axis, machining time and machining gap, on material removal rate of glass. The results indicate that the feed rate of the worktable at horizontal direction has less effect on material removal rate, which shows a fluctuation phenomenon within a certain range. The feed rate of the Z axis directly influences the machining gap and leads to a remarkable change on material removal rate. Larger material removal rate can be obtained when the feeding frequency of Z direction is one time per processing. With the increase of rotation speed of the tool, material removal rate increases firstly and decreases afterwards, and it gets the maximum value with the rotation speed of 4800 rev/min. The machining time is directly proportional to material removal amount, but inversely proportional to material removal rate. Furthermore, material removal rate decreases with the increase of the machining gap between the tool and the workpiece. On the basis of above, the machining mode with the tiny-grinding wheel based on the EMR effect is presented.

Public health as a basic condition for the socio-economic development of the region

2021 ◽  
pp. 18-24
Author(s):  
А.Н. Гайфуллин
Keyword(s):  
Economic Development ◽  
Standard Of Living ◽  
The Public ◽  
Qualitative And Quantitative ◽  
Socio Economic Development ◽  
Quantitative Characteristics ◽  
The Subject ◽  
Health Situation ◽  
Qualitative And Quantitative Characteristics

Социально-экономическое развитие есть планомерная процедура совершенствования уровня жизни, качественных и количественных характеристик, потребляемых общественностью благ. Исходя из ситуации со здоровьем населения в регионе, выставляются соответствующие ориентиры. В разрезе региональной специфики закладываются и реализуются целевые программы, которые одновременно зависят от здоровья населения и направлены, собственно, на улучшение качества его здоровья. Согласно тематике настоящей статьи, ведущий фактор социально-экономического роста - здоровье населения, именно он будет оценен как катализатор искомого регионального развития. Socio-economic development is a systematic procedure for improving the standard of living, qualitative and quantitative characteristics of the goods consumed by the public. Based on the health situation of the population in the region, appropriate guidelines are set. In the context of regional specifics, targeted programs are being laid and implemented, which at the same time depend on the health of the population and are aimed, in fact, at improving the quality of its health. According to the subject of this article, the leading factor of socio-economic growth is the health of the population, it will be evaluated as a catalyst for the desired regional development.

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