scholarly journals Determination of soil density by theoretical and experimental methods

2021 ◽  
Vol 344 (1) ◽  
pp. 60-63
Author(s):  
A. V. Lavrov ◽  
M. A. Litvinov
Keyword(s):  
Soil Moisture ◽  
Harmful Effect ◽  
Soil Density ◽  
Steel Cylinder ◽  
Soil Hardness ◽  
Three Samples ◽  
Before And After ◽  
Almost All ◽  
Maximum Contact

Relevance. According our researches it was found that almost all models oftractors and self-propelled machines has created the maximum contact pressure ofthe movers on the soil above the permissible values. In such way, in view ofthe extreme topicality of the saving soil fertility during evaluating theagrotechnical indicators of a self-propelled selection seeder, it is necessary, first ofall, to make researches to determine the harmful effect of propellers on the soil.Methods. Theoretical researches of determining the soil hardness and density werecarried out using the dependence of density on hardness. During the tests of theself-propelled selection seeder, soil moisture was measured at a depth of 3 inches (7.6 cm) and it was 20%. To measure soil moisture, It was used a digital device, itwas a universal moisture meter TK100. Samples were taken before and after eachpass of the self-propelled seeder with the front and rear wheels. Hardness wasmeasured for each sample.The Kachinskys method was used to measure soil density as the experimentalmethod. To take soil samples, a 100 cubic meter drill (steel cylinder) was used.Soil samples were taken according to the method described above. At the sametime, for each case, three samples were taken to exclude random deviations in soildensity indicators. In the laboratory, the samples were weighed on a VK 3000.1electronic balance with a measurement error of 0.1 grams.Results. The soil density was determined by calculation and experimental methodsin three zones: before the seeder pass and after each its pass in the track behind thefront and rear wheels at a depth of 7.6 cm. The results obtained differ from eachother by a maximum of 6.2%.

Reliability Design and Wear Extent Determination of a Cam Mechanism

2012 ◽  
Vol 268-270 ◽  
pp. 1034-1038
Author(s):  
Yi Yuan Ge ◽  
Jun Fa Wang ◽  
Gui Lian Wang ◽  
Ya Qin Li
Keyword(s):  
Fuzzy Optimization ◽  
Reliability Design ◽  
Cam Mechanism ◽  
Before And After ◽  
Base Circle ◽  
Important Field ◽  
Conventional Optimization ◽  
Maximum Contact ◽  
Mechanical Movement

The application of the cam mechanism is an important field in agricultural machinery since it can realize complex mechanical movement. The wear extent and action reliability of the cam affect the performance and accuracy of the mechanism. The paper combined reliability optimal design and tribology to build a fuzzy optimization model, with minimum of the cam base circle radius and minimum of the maximum contact stress as the objective functions. Compared with conventional optimization, the cam weight was reduced by 11.7%, the stress was increased by 1.96%, and the reliability increased 0.71%. Contrast tests were designed to determine the wear extent before and after optimization. The results prove the feasibility of optimization.

scholarly journals Rockwell Hardness Testing of Pure Nickel Collimators for BNCT Application

2019 ◽  
Vol 36 (1) ◽  
pp. 23-27
Author(s):  
Erasmus Prakasita ◽  
Yohanes Sardjono ◽  
Budi Setyahandana
Keyword(s):  
Centrifugal Casting ◽  
Hardness Test ◽  
Hardness Testing ◽  
Hardness Number ◽  
Boron Neutron Capture ◽  
Material Hardness ◽  
Before And After ◽  
The Difference ◽  
Almost All

In this study, Rockwell and Brinell hardness testing was used to examine material hardness. These methods were chosen because they are easy to carry out, relatively inexpensive, and almost all sizes and shapes can be tested, in which nickel hardness before and after centrifugal casting are identified and compared. These tests enable the determination of the hardness numbers of nickel collimators using for boron neutron capture therapy. The samples were five nickel plates with a dimension of 4.5 × 4.5 cm and five collimators. The collimators were cylindrical and made using centrifugal casting. The basic principle of the hardness test was to apply loading on the object being tested. The Rockwell test was used to assess the material's hardness from the difference of indentation depth, while the Brinell test was used to determine the hardness from the diameter of indentation. From the results of this test, the hardness number of nickel before centrifugal casting is 168.53 BHN or 86.13 HRB, while the hardness number after centrifugal casting is 115.68 BHN or 64.84 HRB. It can therefore be concluded that centrifugal casting decreased nickel hardness.

Theoretical and Experimental Evaluation of Impact on Soil by Wheel Drives of the Self-Propelled Seeder

2020 ◽  
pp. 139-163
Author(s):  
Alexandr Vladimirovich Lavrov ◽  
Maksim Nikolaevich Moskovskiy ◽  
Natalia Sergeevna Kryukovskaya
Keyword(s):  
Contact Pressure ◽  
Contact Area ◽  
Experimental Methods ◽  
The Self ◽  
Soil Density ◽  
Axial Loads ◽  
Soil Hardness ◽  
Different Depths ◽  
Maximum Contact ◽  
Maximum Discrepancy

Dedicated vertical axial loads on the soil from the wheels of a self-propelled seed drill, the area of the contact patch, the maximum contact pressure for the front and rear wheels and the density of the soil are determined by evaluations and experimental methods. The discrepancy between the theoretical and experimental indicators was: 1.4% and 2.0% for the rear and front wheels in vertical axial loads; 2.8% and 2.2% for the rear and front wheels by the contact area of the tires of the seeder with the soil and the maximum contact pressure; 6.2% – the maximum discrepancy on the values of soil density at a depth of 7.6 cm. Soil hardness was measured in three zones: before the seeder's passage and after each of its passage in a rut behind the front and rear wheels at six different depths, determined by the marks on the soil densimeter tester density. Graphics of dependencies of soil hardness on the depth of measurement were constructed.

scholarly journals Staphylococcus aureus of raw cow's milk

2021 ◽  
Vol 23 (102) ◽  
pp. 53-59
Author(s):  
M. D. Kukhtyn ◽  
Y. V. Horiuk ◽  
V. Z. Salata ◽  
V. T. Klymyk ◽  
N. M. Vorozhbit ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Raw Milk ◽  
Cow’S Milk ◽  
Cow's Milk ◽  
Milk Samples ◽  
Before And After ◽  
Pure Cultures ◽  
Almost All

The presence of Staphylococcus aureus in raw milk is considered a direct danger to consumers. Almost all types of dairy products normalize the amount of Staphylococcus aureus in 1 g (cm3) of product, due to their ability to produce thermostable enterotoxins. The aim of the study was to investigate the role of incision of teats of healthy and sick mastitis cows and milking equipment for irradiation of cow's milk with Staphylococcus aureus. Sanitation of milking equipment in farms was carried out with alkaline detergents based on sodium hypochlorite and acid based on phosphoric acid. Blood agar with 5 % sodium chloride was used to isolate staphylococci from washes and milk. Species identification of pure cultures of staphylococci was performed using RapID Staph Plus kits. At the same time before and after milking the skin of teats with Udder Wash and Udder Forte reduces the incidence of Staphylococcus aureus to 4.1 ± 0.3 % of cases. Quantitative determination of staphylococci, including golden on the skin of the teats revealed a decrease in the latter from 283.5 ± 21.2 to 27.6 ± 2.1 CFU/cm3 flush after milking. It has been established that the number of staphylococci, including golden, on the skin of teats increases sharply under subclinical or clinical ointment. Thus, it was found that in the subclinical form of staphylococcal mastitis from the skin of teats isolated S. aureus in the amount of 790.6 ± 65.4 CFU/cm3 of wash. At the same time, in the clinical form of mastitis, the amount of S. aureus increased, on average to 8 thousand CFU/cm3 of flush. It was found that under the condition of sanitary treatment of milking equipment with alternate use of alkaline and acid detergents and disinfectants, only 25 % of washes were staphylococci, and gold – up to 5 % of samples. It was found that in 43.7 ± 3.9 % of raw milk samples Staphylococcus aureus was not detected in 1 cm3. The number of milk samples containing Staphylococcus aureus up to 100 CFU/cm3 was 39.1 ± 3.3 %, and 17.2 ± 1.4 % of milk samples were contaminated with Staphylococcus aureus in the amount of 101 to 200 CFU/cm3. Therefore, the presence of more than 200 CFU/cm3 in freshly milked Staphylococcus aureus in milk indicates the ineffectiveness of antimastitis measures, skin remediation of teats and sanitation of milking equipment.

scholarly journals Forensic examination of effects of rheumatoid arthritis on handwriting characteristics

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Komal Saini ◽  
Bhavya Sharma ◽  
Manpreet Kaur
Keyword(s):  
Rheumatoid Arthritis ◽  
Qualitative Analysis ◽  
Forensic Examination ◽  
Before And After ◽  
Almost All ◽  
Document Examiners ◽  
Huge Variation

Abstract Background Rheumatoid arthritis is known to produce deformity of the joints and muscles which can affect the handwriting of an individual significantly. Examination of such handwriting specimens can become a challenging task for the document examiners. This can affect the accuracy of their opinions upon the related cases. Thus, the present study was conducted to determine the effects of rheumatoid arthritis on handwriting characteristics qualitatively and statistically. The study also included qualitative analysis and comparison of line quality defects of copied writings and writings affected by rheumatoid arthritis. Results Handwriting characteristics were analyzed qualitatively and statistically in old writings vs affected writings. All these handwriting characteristics were also analyzed qualitatively in copied writings vs affected writings. The results of the study showed significant deteriorating effects of rheumatoid arthritis on almost all handwriting characteristics, except for characteristics such as slant, retouching, and overwriting. The pictorial appearance of letters in the writings executed before and after the onset of illness was even observed to appear different altogether in case of some individuals with severely affected writings. Moreover, the analysis of copied writings indicated the execution of writing by a different person. Handwriting characteristics such as slant, spacing, and alignment were observed to show insignificance in analyzing differences between copied and genuine writings affected by the illness. Conclusion It has been concluded that rheumatoid arthritis causes deterioration of letters, tremor, disturbed rhythm, and a huge variation in other handwriting characteristics. The copied writings have also presented line quality defects like artificial tremor, hesitations, retouching, and unnatural pen lifts at all wrong places. The determination of these peculiarities may assist the document examiners in the differentiation of copied and affected writings.

scholarly journals The determination of soil moisture and soil density in situ by neutron and γ-ray scattering

1967 ◽  
Vol 8 (2) ◽  
pp. 55-70
Author(s):  
Takaaki Ando ◽  
Teruo Aihara ◽  
Takao Kanai ◽  
Keiichi Kodai ◽  
Akira Unosawa
Keyword(s):  
Soil Moisture ◽  
Soil Density ◽  
Γ Ray ◽  
Ray Scattering

scholarly journals Estimation of Environmental Risk when Eating Raw and Boiled Vegetables

2019 ◽  
Keyword(s):  
Heavy Metals ◽  
Heat Treatment ◽  
Environmental Risk ◽  
Chemical Elements ◽  
Atomic Absorption Spectrophotometry ◽  
Hazard Ratios ◽  
Before And After ◽  
High Concentrations ◽  
Almost All

The risk to human health due the consumption of vegetables is based on the characterization of harmful effects that can develop in the human body in case of the long-term eating of these products. At the same time, when people consume vegetables, it is possible to reduce their content of pollutants by heat treatment, for example, cooking. Therefore, it is relevant to compare the risk that occurs when eating raw and boiled vegetables. Purpose. Determination of environmental risk from the eating of vegetables (carrots and potatoes) with high concentrations of chemical elements and the ability to reduce them in case of boiling. Methods. Field, atomic absorption spectrophotometry, statistical methods were used. Results. On the basis of field-based research, the content of heavy metals - lead, cadmium, zinc, copper and iron and nitrates in cooked and raw carrots and potatoes - was determined on the farmland located in Shevchenkovo settlement of the Kharkiv region and laboratory studies. It turned out that virtually all metals concentrations do not have excessived MAC. To determine the level of influence of cooking on the fruit the relative content of heavy metals before and after cooking were researched. Based on the results of laboratory analysis, the coefficients of concentration of heavy metals in plant products were calculated and the environmental risk from the consumption of vegetables in food was calculated. When comparing all risk agents among themselves by hazard ratios, the predominance of nitrates and cadmium in all samples was detected. It should also be noted that there is a high risk of lead, copper and iron found in carrots. Comparison of test objects with the overall environmental risk for health from their use showed that the highest risk is crude carrots, and the lowest - potatoes are cooked. Heat treatment of carrots reduces the overall risk by only 25%, and potato - by 40%. Conclusions. It is established that after heat treatment almost all substances are partially derived from vegetables. Analysis of the changes occurring in potatoes and carrots after cooking indicates a reduction in the risk of the disease. The risk of the onset of diseases in virtually all organs is highest when carrots are consumed raw.

scholarly journals Application of the TDR Soil Moisture Sensor for Terramechanical Research

Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 2116 ◽  
Author(s):  
Jarosław Pytka ◽  
Piotr Budzyński ◽  
Mariusz Kamiński ◽  
Tomasz Łyszczyk ◽  
Jerzy Józwik
Keyword(s):  
Soil Moisture ◽  
Optimal Solution ◽  
Time Domain Reflectometry ◽  
Moisture Sensor ◽  
Soil Moisture Data ◽  
Flight Operations ◽  
Before And After ◽  
Vehicle Mobility ◽  
Field Sensor

This paper presents examples of the application of the TDR (Time-Domain Reflectometry) sensor in terramechanical research. Examples include the determination of soil moisture content during off-road vehicle mobility tests, the determination of snow density before and after the wheeling of a snow grooming machine and an airplane, as well as the monitoring of turf moisture on a grassy airfield for the analysis and prediction of safe and efficient flight operations (takeoff and landing). A handheld TDR meter was used in these experiments. Soil moisture data were correlated with the vehicle mobility index and a simple model for this correlation was derived. Using grassy airfield research, soil moisture data were related to meteorological impacts (precipitation, sunlight, etc.). Generally, it was concluded that the TDR meter, in its handheld version, was a useful tool in the performed research, but a field sensor that operates autonomically would be an optimal solution for the subject applications.

The Plasmin Inhibitors of Plasma

1964 ◽  
Vol 12 (01) ◽  
pp. 119-125 ◽  
Author(s):  
Y Shamash ◽  
A Rimon
Keyword(s):  
Human Plasma ◽  
New Method ◽  
Normal Amount ◽  
Caseinolytic Activity ◽  
Before And After ◽  
Plasmin Inhibitors

SummaryA new method for the assay of plasmin inhibitors in human plasma is described. The method consists of determination of the caseinolytic activity of a standard plasmin solution before and after incubation with the inhibitor, with lysine added to the mixture as a stabilizer of plasmin. Using this method, it was found that plasma contains enough inhibitors to inactivate 30 caseinolytic units of plasmin, or 10 times the normal amount of plasminogen in human plasma.

FRACTIONAL DETERMINATIONS OF URINARY 17-KETOSTEROIDS IN HYPEREMESIS GRAVIDARUM

1962 ◽  
Vol 41 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Pentti A. Järvinen ◽  
Sykkö Pesonen ◽  
Pirkko Väänänen
Keyword(s):  
Hyperemesis Gravidarum ◽  
First Trimester ◽  
Control Group ◽  
Before And After ◽  
Daily Urine ◽  
First Trimester Of Pregnancy ◽  
The Difference

ABSTRACT The fractional determination of 17-ketosteroids in the daily urine was performed in nine cases of hyperemesis gravidarum and in four control cases, in the first trimester of pregnancy both before and after corticotrophin administration. The excretion of total 17-KS is similar in the two groups. Only in the hyperemesis group does the excretion of total 17-KS increase significantly after corticotrophin administration. The fractional determination reveals no difference between the two groups of patients with regard to the values of the fractions U (unidentified 17-KS), A (androsterone) and Rest (11-oxygenated 17-KS). The excretion of dehydroepiandrosterone is significantly higher in the hyperemesis group than in the control group. The excretion of androstanolone seems to be lower in the hyperemesis group than in the control group, but the difference is not statistically significant. The differences in the correlation between dehydroepiandrosterone and androstanolone in the two groups is significant. The high excretion of dehydroepiandrosterone and low excretion of androstanolone in cases of hyperemesis gravidarum is a sign of adrenal dysfunction.

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