scholarly journals DEVELOPMENT OF INSTRUMENTAL MODULE FOR OUTWARD IRREGULAR POLISHING WITH ACTIVATING LUBRICATING-COOLING LIQUIDS (LCL )

2021 ◽  
pp. 3-19
Author(s):  
Анатолій Fesenko ◽  
Fatyma Yevsiukova ◽  
Olena Naboka ◽  
Mariia Kolisnyk ◽  
Yevhen Honcharov
Keyword(s):  
Superficial Layer ◽  
Operating Properties ◽  
Large Probability

Quality of superficial layer of details of machines, qualificatory them operating descriptions in most cases are formed at polishing. This process is characterized high thermal tension and large probability of appearance in the superficial layers of the polished details of defects as прожогов and микротрещин, reducing their operating properties.              One of ways of decline of thermal tension of process of polishing and improvement of quality of the polished details are the use of rational charts of treatment and application of effective compositions of lubricating-cooling liquids (LCL). For realization of these terms the instrumental module of collapsible diamond-impregnated for the round outward polishing, using the methods of irregular treatment, is in-process worked out, providing a serve  LCL in the zone of cutting and her activating in кавитационных attachments. His construction allows to improve penetration LCL in the zone of contact of diamond-impregnated with a purveyance, that results in reduction of теплонапряженности process and improvement of quality of surface at the increase of the productivity of treatment. The effect of the irregular polishing is got with admission LCL  through abrasive bars and interval between them.

Study of Residual Stresses Distribution Generated from Milling of Magnesium Alloy Parts

2014 ◽  
Vol 657 ◽  
pp. 18-22 ◽  
Author(s):  
Bogdan Chirita ◽  
Nicolae Catalin Tampu
Keyword(s):  
Mechanical Properties ◽  
Magnesium Alloy ◽  
Residual Stresses ◽  
Surface Quality ◽  
Specific Weight ◽  
Superficial Layer ◽  
Medical Industry ◽  
Alloy Part

Magnesium alloys exhibit a very good ratio of mechanical properties versus specific weight, thus making it an important choice for parts used in automotive, aeronautic and medical industry. The distribution of residual stress in the superficial layer of the material is regarded as one of the factors defining the surface quality of a machined part. It is therefore important to know this distribution as it is closely related to fatigue and corrosion resistance, especially for the parts working in aggressive environments (i.e. biomedical devices). The present paper focuses on the determination of the residual stresses induced in a magnesium alloy part processed by milling, and their effects on surface quality.

scholarly journals EFFECTS OF STORAGE CONDITIONS FOR LARGE ROUND BALES ON QUALITY OF GRASS-LEGUME HAY

1989 ◽  
Vol 69 (4) ◽  
pp. 955-961 ◽  
Author(s):  
L. F. LAFLAMME
Keyword(s):  
Storage Time ◽  
Storage Conditions ◽  
Superficial Layer ◽  
Chemical Components ◽  
Sample Storage ◽  
Plastic Bag ◽  
Large Round ◽  
Storage Methods

Two experiments were conducted to assess the effects of storage conditions on the quality of large round bales (LRB). Samples were taken at 75-d intervals from LRB stored inside, outside single bales covered with a 15-mm black polyethylene plastic bag, outside uncovered as single bales, outside uncovered in a single row and outside uncovered in a double stacked row. Bales were sampled at depths of 0–15, 15–30 and 30–45 cm. Time, storage and depth factors had an influence on the chemical components of the LRB except for protein. Weathering had the most effect after 150 d of storage and with LRB stored uncovered and in the top 15-cm layer. Significant (P < 0.05) interactions in in vitro dry matter digestibilities were found for storage time × depth of sample, storage time × storage methods and for depth of sample × storage methods. Under the conditions of our experiments, weathering damages were limited to the superficial layer of LRB left uncovered. Key words: Large round bales, weathering, storage, moisture

scholarly journals ANALYSIS OF THE CHEMICAL ATTRIBUTES OF A TYPIC HAPLUDULT SOIL UNDER FOREST SYSTEMS

FLORESTA ◽  
2021 ◽  
Vol 51 (2) ◽  
pp. 447
Author(s):  
David Silva Gomes ◽  
Cláudio Roberto Marciano ◽  
Lucas Luís Faustino
Keyword(s):  
Secondary Forest ◽  
Superficial Layer ◽  
Soil Samples ◽  
Acacia Auriculiformis ◽  
Leguminous Tree ◽  
Inga Edulis ◽  
Chemical Attributes ◽  
Agronomic Quality ◽  
Janeiro State

The aim of this study was to evaluate the chemical quality of a Typic Hapludult soil under secondary forest (capoeira), pasture and three leguminous tree species: Acacia auriculiformis, Mimosa caesalpiniaefolia and Inga edulis, in Conceição de Macabú County, Rio de Janeiro State, Brazil, implemented in December 1998. Soil samples from the 0-0.10 and 0.10-0.20 m layers were collected and analyzed in July/2015. The C content in the 0.10 m layer was higher in capoeira and lower in the pasture. The CECef and CECpH=7 values and the N, P, Ca, Mg and K levels were lower in pasture, higher in Acacia auriculiformis or capoeira, and intermediate in Inga edulis and Mimosa caesalpiniaefolia. The chemical variables regarding the vegetation cover generally had the lowest values in the pasture, the highest in the Acacia auriculiformis or capoeira, and intermediate values in Inga edulis and Mimosa caesalpiniaefolia. It was concluded that revegetation leads to changes in the superficial layer of the soil which make its attributes closer to those of capoeira and further away from those of pasture, indicating an increase in quality to support the functioning of a forest ecosystem, despite the worsening of some Agronomic quality indicators.

Adhesion Characterisation of Complex Ceramics Thin Layers Deposited on Metallic Substrate

2017 ◽  
Vol 907 ◽  
pp. 126-133
Author(s):  
Costel Florea ◽  
Costică Bejinariu ◽  
Cristian Savin ◽  
Bogdan Istrate ◽  
Marcelin Benchea ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Good Control ◽  
Ceramic Materials ◽  
Superficial Layer ◽  
Thin Layers ◽  
Good Adhesion ◽  
Micro Cracks ◽  
Scratch Tests ◽  
2D And 3D

There was obtained superficial layer of ceramic (made of complex oxides 80% yttrium oxide stabilized zirconium ZrO2/8%Y2O3 (Metco 204B-NS) and 20% alumina Al2O3 (Metco 105SFP)) by plasma jet deposition at a temperature of 12000°C of particles, on substrates of iron FC250. The layers were obtained by five successive passages (60 μm thick) on samples with different surface roughness and different processed (0.34, 2.47 și 4.25 μm). For the analysis of the adhesion of ceramic layers to the substrate scratch tests were carried out and the traces analyzed by scanning electron microscopy (SEM 2D and 3D), chemical analysis EDS, and profilometry. In conclusion, it was obtained compact layers on the samples 2 and 3 with micro-cracks on the surface due to thermal gradient that occurs between the layers deposited during the five passes. Regarding the resistance, the sample with the higher roughness (sample 3) resisted most to exfoliation the layer (15 N) in contrast to the sample 2 of 14N and only 10N for the polished sample. It can be concluded that there is a dependency between the surface roughness and the thickness of layer deposited. Scratch marks presents no cracks, pores or adjacent exfoliation. The results show that the technique is suitable for obtaining thin layers of ceramic materials with a very good control of the thickness, very good adhesion to the substrate and a direct relationship between surface roughness and the quality of deposited layer.

scholarly journals Oxisol physical quality with application of landfill leachate

2017 ◽  
Vol 38 (5) ◽  
pp. 2967
Author(s):  
Jean Carlo Santos de Oliveira ◽  
José Francirlei de Oliveira ◽  
Alex Figueiredo ◽  
Graziela Moraes de Cesare Barbosa ◽  
João Tavares Filho
Keyword(s):  
Landfill Leachate ◽  
Weighted Average ◽  
Mineral Fertilizer ◽  
Field Capacity ◽  
Superficial Layer ◽  
Soil Density ◽  
Physical Quality ◽  
Analysis Of Stability ◽  
Aeration Capacity

The organic carbon present in the landfill leachate (LL) can improve the physical quality of the soil when applied in agricultural areas, minimizing the problem of disposal of this waste. The objective of this work was to evaluate the effect of the application of different doses of LL on the physical quality of the Red Latosol (Oxisol) after five years of applications. The treatment consisted of applications of LL in doses of 32, 65, 98 and 130 m3 ha-1 crop-1 and the treatment that receives mineral fertilizer. The physical quality of the soil was evaluated in soil samples collected in the layers 0.00-0.10 and 0.10-0.20 m, through the analysis of stability and diameter of the aggregates, soil density, total aeration capacity, field capacity and available water content. After five years of application of LL, at doses of 65, 98 and 130 m3 ha-1 crop-1 have promoted a linear increase of the aggregates with diameter greater than 2.00 mm, of the weighted average and geometric diameters and of the soil density, with a consequent reduction of the ratio between macro and micropores and the aeration capacity of the layers 0.00-0.10 and 0.10-0.20 m. After five years of these applications, the soils that received the dose of 32 m3 ha-1 crop-1 presented the best physical quality in relation to the other doses, since this dose did not promote an increase of the aggregates larger than 2 mm in the superficial layer (0.00-0.10 m) and was the dose with lower effect in the reduction of aeration of the soil, in relation to the others (65, 98 and 130 m3 ha-1 season-1) in the layers 0.00-0, 10 and 0.10 - 0.20 m.

scholarly journals Soil organic carbon in a toposequence in the semiarid of Paraíba, Brazil

2020 ◽  
Vol 9 (5) ◽  
pp. e164953365
Author(s):  
Cheila Deisy Ferreira ◽  
Francisco Tibério de Alencar Moreira ◽  
Patrícia Carneiro Souto ◽  
Lyanne dos Santos Alencar ◽  
César Henrique Alves Borges
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Carbon Content ◽  
Soil Analysis ◽  
Superficial Layer ◽  
The Other ◽  
Organic Carbon Content ◽  
Physical And Chemical ◽  
Upper Third

Organic carbon is a sensible indicator to evaluate the environmental quality of the soil. The objective of this study was to evaluate the organic carbon content of the soil in a toposequence in Serra do Teixeira, municipality of Teixeira, PB. Soil samples were collected in the upper third (UT), upper middle third (UMT), lower middle third (LMT) and lower third (LT) on three depths (0-5, 5-10 and 10-20 cm), with five replicates for each depth, resulting in a total of 60 samples. The organic carbon was evaluated using the methodology of Walkey-Black. Physical and chemical soil analysis were also carried out. The highest mean of carbon content was found in the first 5 cm (19.83 g dm-3), significantly differing from the other depths. It was also observed that the mean content of soil organic carbon on LMT was significantly higher than the other thirds, with 19.39 g dm-3. It is concluded that the highest contents of organic carbon are found on the most superficial layer of the soil. The organic carbon content variations found along the toposequence indicates influence of the relief and the anthropic action.

scholarly journals PRACTICAL REALIZATION OF METHODOLOGY OF PROCESS CONTROL OF TOOLING

2020 ◽  
pp. 91-102
Author(s):  
Natalia Veselovska
Keyword(s):  
Process Control ◽  
High Efficiency ◽  
Structural Features ◽  
High Rate ◽  
Component Part ◽  
Parallel Kinematics ◽  
Operating Properties ◽  
Treatment Complication ◽  
Productive Systems

The problem of providing of necessary quality and exploitation of properties of details of machines acquires an all more important value in an engineer. However to present tense the not worked out is generalized theoretical dependences between the parameters of quality of surface, exactness of treatment, operating properties of details and parameters of processes of tooling, that allow to decide the task of the technological providing of the set operating properties of details. Process control of forming of surface with necessary properties comes true mainly by the use of partial experimental dependences and tables of the modes of treatment. Complication of problem consists in that at treatment of details it is necessary to set such terms of treatment, that would provide the complex of requirements in relation to the wear of instrument, exactness of treatment, to descriptions of quality of surface, productivity and others like that. The areas of the most effective use of the productive systems are foremost determined by a technological equipment that is component part by the nomenclature of workparts and CAS of management. Experience of development and exploitation of mechanisms of parallel kinematics confirms them high efficiency and perspective of this direction of engineer. As a result of structural features of arrangement, the mechanisms of parallel kinematics have the reserved kinematics chains that form spatial structures. As a rule these structures are founded on the base of the three-cornered cored systems. They have high rigid descriptions, provide high-rate and accelerations of working organs. Accordingly given an opportunities it is allowed by substantial character to promote static and dynamic exactness of positioning of mechanisms. Wide introduction of mechanisms of parallel kinematics absence of theoretical bases of development of mechanisms interferes with, in particular mechanisms of an increase exactness. The increase of exactness needs complex research of kinematics and working processes that take place in their basic knots. Therefore researches are sent to the increase of parameters of static and dynamic exactness of spatial mechanisms of parallel kinematics is actual.

Comparative Study Concerning the Generation of some Circular Grooves by Radial Cold Rolling with Roller Tools and Cutting

2014 ◽  
Vol 1036 ◽  
pp. 246-251
Author(s):  
Eduard Niţu ◽  
Monica Iordache ◽  
Doina Iacomi
Keyword(s):  
Comparative Analysis ◽  
Cold Rolling ◽  
Economic Efficiency ◽  
Superficial Layer ◽  
Point Of View ◽  
Micro Hardness ◽  
Circular Profile ◽  
Materials Used ◽  
Cementation Steel

This study is part of the concerns that the authors have had in recent years, representing an extension of a research project funded consisting in modelling representative cold rolling processes of profiles. This paper presents a comparative analysis of quality of the superficial layer of a circular profile (grooves) obtained by two different processes: radial rolling with two roller tools and turning with radial feed. Also, the two processes are compared from the viewpoint of economic efficiency. The materials used for the experiments are frequently used to obtain pieces with circular grooves: two types of cementation steel and two types of heat treatable steel. The characteristics of the superficial layer which describe its quality and which are comparatively analyzed in connection to the two processes are: roughness, microstructure and micro-hardness. The economic efficiency of the two processes was assessed by means of the costs implied and the productivity of processing. The interpretation of the results obtained enabled stressing the advantages to generate circular grooves by cold radial rolling from the point of view of the quality of the superficial layer of pieces, as well as the limits of the use of this process from the viewpoint of economic efficiency.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

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