PRINCIPLES OF BUILDING OF AUTOMATIC MEASURING VOLUME OF AGRICULTURAL PRODUCTS AND MATERIALS DEVICES

1970 ◽  
pp. 68-71
Author(s):  
A. M. Sedov
Keyword(s):  
Free Volume ◽  
Rational Design ◽  
Experimental Studies ◽  
Agricultural Products ◽  
Static Characteristics ◽  
Basic Principles ◽  
Tuning Parameters ◽  
Quantitative Properties ◽  
Automation Tools ◽  
Analytical Expressions

Many qualitative and quantitative properties of products, materials, and parameters of technological processes in agricultural production and other sectors of the economy are characterized by volume indicators. Based on analytical and experimental studies a unified system of automatic volumetric meters has been developed taking into account three basic principles: “discharge” of a gas-filled chamber to a measuring capacity; generation of a linearly increasing pneumatic signal in the free volume of the measuring capacitance; digital quantization of the free volume of the measuring capacitance. The system is unified by the elemental base, power levels and output signals and allows you to solve the main tasks of measuring, monitoring and signaling the volume of most agricultural products and materials; create fundamentally new automation tools from standardized units on the basis of the volumetric module by adding other modules (weighting, computing, differentiating, comparisons, etc.). Analytical expressions of the static characteristics of the developed volumes are obtained experimental studies have confirmed their reliability. The rational design and tuning parameters of the devices are determined taking into account the specifics of the physical properties of agricultural products and materials.

Actual issues of hygienic regulation and creation of safe working conditions at pharmaceutical manufacturing enterprises

2020 ◽  
Vol 60 (10) ◽  
pp. 640-644
Author(s):  
Vadim M. Vasilkevich ◽  
Ruslan V. Bogdanov ◽  
Elena V. Drozdova
Keyword(s):  
Pharmaceutical Industry ◽  
Working Conditions ◽  
Experimental Studies ◽  
Pharmaceutical Products ◽  
Laboratory Animals ◽  
Production Environment ◽  
Basic Principles ◽  
Toxicological Studies ◽  
Health Disorders ◽  
Safe Working

Introduction. The working conditions of pharmaceutical industry workers are characterized by the combined effect of unfavorable factors of the production environment, among which the leading one is chemical. The aim of study is to substantiate the basic principles and criteria for hygienic regulation of pharmaceutical products in their production to ensure safe working conditions for employees based on the results of their own research and existing requirements of technical regulations. Materials and methods. Analysis of working conditions and the prevalence of health disorders in pharmaceutical workers (according to literature data), toxicological studies of pharmaceutical substances on laboratory animals, scientific justification of hygiene standards in the air of the working area. Results. Among employees of the pharmaceutical industry, the predominant forms of production-related health disorders are diseases of the respiratory system, as well as skin dermatitis of allergic origin, liver and biliary tract diseases. Based on the results of experimental studies of domestic pharmaceutical products for the treatment of cardiovascular, oncological and mental diseases that have priority socio-economic significance, the basic principles and features of the practice of justifying the hygienic standards of medicines in the air of the working area are developed and systematized. Conclusions. During hygienic rationing of medicines, it is necessary to use a differentiated approach that allows, based on the analysis of information about the chemical structure, physical and chemical characteristics, production conditions, pharmacotherapeutic activity, and the results of studying the toxic effect in an experiment on laboratory animals, to determine the maximum permissible content in the air of the working area of medicines or to justify the prohibition of isolation with reasoned recommendations for their safe production.

scholarly journals Effect of an Improved Yasutomi Pressure-Viscosity Relationship on the Elastohydrodynamic Line Contact Problem

2013 ◽  
Vol 2013 ◽  
pp. 1-7
Author(s):  
Vincenzo Petrone ◽  
Adolfo Senatore ◽  
Vincenzo D'Agostino
Keyword(s):  
High Pressure ◽  
Film Thickness ◽  
Free Volume ◽  
Experimental Studies ◽  
Line Contact ◽  
Volume Model ◽  
Free Volume Model ◽  
Pressure Area ◽  
New Formulation ◽  
Lubricant Viscosity

This paper presents the application of an improved Yasutomi correlation for lubricant viscosity at high pressure in a Newtonian elastohydrodynamic line contact simulation. According to recent experimental studies using high pressure viscometers, the Yasutomi pressure-viscosity relationship derived from the free-volume model closely represents the real lubricant piezoviscous behavior for the high pressure typically encountered in elastohydrodynamic applications. However, the original Yasutomi correlation suffers from the appearance of a zero in the function describing the pressure dependence of the relative free volume thermal expansivity. In order to overcome this drawback, a new formulation of the Yasutomi relation was recently developed by Bair et al. This new function removes these concerns and provides improved precision without the need for an equation of state. Numerical simulations have been performed using the improved Yasutomi model to predict the lubricant pressure-viscosity, the pressure distribution, and the film thickness behavior in a Newtonian EHL simulation of a squalane-lubricated line contact. This work also shows that this model yields a higher viscosity at the low-pressure area, which results in a larger central film thickness compared with the previous piezoviscous relations.

Numerical and experimental studies on the thermal and static characteristics of multi-leaf foil thrust bearing

2021 ◽  
pp. 135065012110110
Author(s):  
Yu Guo ◽  
Yu Hou ◽  
Qi Zhao ◽  
Xionghao Ren ◽  
Shuangtao Chen ◽  
...  
Keyword(s):  
High Speed ◽  
Thrust Bearing ◽  
Load Capacity ◽  
Failure Process ◽  
Experimental Studies ◽  
Elastic Model ◽  
Static Characteristics ◽  
Bearing Load ◽  
Foil Thrust Bearing ◽  
Cooling Air

Foil bearing is considered to be a promising supporting technology in high-speed centrifugal machinery. Due to the high-speed shearing effect in the viscous lubricant film, heat generation could not be ignored. In this paper, a thermo-elastic model of the multi-leaf foil thrust bearing is proposed to predict its thermal and static characteristics. In the model, modified Reynolds equation, energy equation, and Kirchhoff equation are solved in a coupling way. The contact area between the foil and welding plate is taken into account. Besides, the effect of cooling air on the bearing temperature is investigated. The ultimate load capacity and transient overload failure process of the bearing is analyzed and discussed. The effect of rotation speed on the bearing temperature is more obvious than that of the bearing load. The bearing temperature drops obviously by introducing the cooling air, and the cooling effect is improved with the supply pressure. The transient overload failure of the bearing occurs when the bearing load exceeds the ultimate value.

scholarly journals ОЦІНКА ПОКАЗНИКІВ КОМФОРТНОСТІ БІЛИЗНЯНИХ ТРИКОТАЖНИХ ПОЛОТЕН ДЛЯ ЗАНЯТЬ СПОРТОМ

2019 ◽  
Vol 136 (4) ◽  
pp. 106-114
Author(s):  
С. І. Арабулі ◽  
А. Т. Арабулі ◽  
С. С. Ототюк ◽  
В. В. Клочко ◽  
Д. Ю. Черепенко
Keyword(s):  
Physical Properties ◽  
Materials Science ◽  
Experimental Studies ◽  
Basic Principles ◽  
Textile Materials ◽  
Clothing Comfort ◽  
Modern Methods

Determination  of  comfort properties  of  knitted  underwear for  sports and  comparison  of traditional and innovative underwear for thermal underwear. Methodology.  The  article  provides  an  analysis  of  the  modern  range  of  textile  materials  for underwear, analyzes the latest developments in the design of thermal underwear. The modern methods have been used to determine clothing comfort and physical properties of textile materials. Experimental studies are based on the basic principles of textile materials science.

scholarly journals Molecular Dynamics Simulation and Kinetic Study of Fluoride Binding to V21C/V66C Myoglobin with a Cytoglobin-like Disulfide Bond

2020 ◽  
Vol 21 (7) ◽  
pp. 2512
Author(s):  
Lu-Lu Yin ◽  
Jia-Kun Xu ◽  
Xiao-Juan Wang ◽  
Shu-Qin Gao ◽  
Ying-Wu Lin
Keyword(s):  
Molecular Dynamics ◽  
Disulfide Bond ◽  
Rational Design ◽  
Double Mutant ◽  
Md Simulation ◽  
Experimental Studies ◽  
Heme Iron ◽  
Dynamics Simulation ◽  
Fluoride Ion ◽  
Artificial Proteins

Protein design is able to create artificial proteins with advanced functions, and computer simulation plays a key role in guiding the rational design. In the absence of structural evidence for cytoglobin (Cgb) with an intramolecular disulfide bond, we recently designed a de novo disulfide bond in myoglobin (Mb) based on structural alignment (i.e., V21C/V66C Mb double mutant). To provide deep insight into the regulation role of the Cys21-Cys66 disulfide bond, we herein perform molecular dynamics (MD) simulation of the fluoride–protein complex by using a fluoride ion as a probe, which reveals detailed interactions of the fluoride ion in the heme distal pocket, involving both the distal His64 and water molecules. Moreover, we determined the kinetic parameters of fluoride binding to the double mutant. The results agree with the MD simulation and show that the formation of the Cys21-Cys66 disulfide bond facilitates both fluoride binding to and dissociating from the heme iron. Therefore, the combination of theoretical and experimental studies provides valuable information for understanding the structure and function of heme proteins, as regulated by a disulfide bond. This study is thus able to guide the rational design of artificial proteins with tunable functions in the future.

Position Kinematics of a Three-Limbed Mixed Mechanism

1994 ◽  
Vol 116 (3) ◽  
pp. 924-929 ◽  
Author(s):  
M. Husain ◽  
K. J. Waldron
Keyword(s):  
Rational Design ◽  
Industrial Robots ◽  
Parallel Structure ◽  
General Mechanism ◽  
Static Characteristics ◽  
Serial Chain ◽  
Hybrid Mechanism ◽  
Parallel Structures ◽  
Industrial Use ◽  
Mixed Mechanism

Although robotics has traditionally focused on the serial chain structures typical of industrial robots, fully parallel structures such as the Stewart Platform have also found considerable industrial use. Actively coordinated mechanisms which have combinations of serial and parallel characteristics have been practically employed, and can be expected to become more important in the future. There has been very little study of the kinematic and static characteristics of these mechanisms which have combinations of the characteristics of fully serial and fully parallel structures. This work addresses the direct and inverse position kinematics of such a hybrid mechanism with combination of serial and parallel structure which has multiple, actively controlled actuators. While not the most general possible configuration, this particular case does include many important features of the general mechanism, and the solution obtained gives useful insight for developing a general theory of forward and inverse kinematics which will be equally applicable to serial, parallel and combination structures. Such a theory is necessary for rational design of hardware and software for such systems.

scholarly journals Main Structural Targets for Engineering Lipase Substrate Specificity

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 747
Author(s):  
Samah Hashim Albayati ◽  
Malihe Masomian ◽  
Siti Nor Hasmah Ishak ◽  
Mohd Shukuri bin Mohamad Ali ◽  
Adam Leow Thean ◽  
...  
Keyword(s):  
Substrate Specificity ◽  
Rational Design ◽  
Molecular Mechanisms ◽  
Experimental Studies ◽  
Random Mutagenesis ◽  
Binding Pocket ◽  
Amino Acid Sequences ◽  
Site Directed Mutagenesis ◽  
Saturation Mutagenesis ◽  
Process Conditions

Microbial lipases represent one of the most important groups of biotechnological biocatalysts. However, the high-level production of lipases requires an understanding of the molecular mechanisms of gene expression, folding, and secretion processes. Stable, selective, and productive lipase is essential for modern chemical industries, as most lipases cannot work in different process conditions. However, the screening and isolation of a new lipase with desired and specific properties would be time consuming, and costly, so researchers typically modify an available lipase with a certain potential for minimizing cost. Improving enzyme properties is associated with altering the enzymatic structure by changing one or several amino acids in the protein sequence. This review detailed the main sources, classification, structural properties, and mutagenic approaches, such as rational design (site direct mutagenesis, iterative saturation mutagenesis) and direct evolution (error prone PCR, DNA shuffling), for achieving modification goals. Here, both techniques were reviewed, with different results for lipase engineering, with a particular focus on improving or changing lipase specificity. Changing the amino acid sequences of the binding pocket or lid region of the lipase led to remarkable enzyme substrate specificity and enantioselectivity improvement. Site-directed mutagenesis is one of the appropriate methods to alter the enzyme sequence, as compared to random mutagenesis, such as error-prone PCR. This contribution has summarized and evaluated several experimental studies on modifying the substrate specificity of lipases.

scholarly journals Research of the hydraulic resistance of the granular filter of the sweeping mashnine

2019 ◽  
Vol 135 ◽  
pp. 01049
Author(s):  
Rashid Sharapov
Keyword(s):  
Hydraulic Resistance ◽  
Experimental Studies ◽  
Air Purification ◽  
Technological Parameters ◽  
Variable Parameters ◽  
Granular Filter ◽  
Modern Cities ◽  
Mathematical Expressions ◽  
Cleaning Equipment ◽  
Analytical Expressions

The article focuses on the need to improve the ecology in modern cities based on the development of new cleaning equipment. It is proposed to use a granular filter as a dust cleaning unit in sweeping machines. The advantages of granular filters over other types of filtering apparatus are given. The basic schemes of working equipment of sweepers are considered. To describe the processes during air purification in the proposed granular filter, mathematical expressions are proposed to determine the hydraulic resistance of the proposed filter. When developing analytical expressions, the structural and technological features of the proposed filter were taken into account. The results of calculating the hydraulic resistance of the proposed granular filter depending on its main structural and technological parameters are obtained. To confirm the obtained analytical expressions, experimental studies were carried out. The clinker of the Belgorod cement plant of a fraction of -10 + 5 mm was selected as the filtering material. During the experiment, cement was used as dust with a specific surface of various dispersion, determined by the parameter δ50. In addition, filtering speed and filtering time are accepted as variable parameters.

scholarly journals Can analytical shading be art?

2015 ◽  
Vol 47 (3) ◽  
pp. 121-135
Author(s):  
Jerzy Siwek ◽  
Wojciech Wacławik
Keyword(s):  
Experimental Studies ◽  
Digital Terrain Model ◽  
Crucial Importance ◽  
Significant Similarity ◽  
Basic Principles ◽  
Factors Affecting ◽  
Terrain Model ◽  
Digital Terrain ◽  
Proper Generalization

Abstract Despite numerous theoretical and experimental studies of analytical relief shading, devised about half a century ago, its quality has not yet reached the excellence of traditional (manual) shading. The paper discusses its basic principles and the main factors affecting the quality of shading. It also stresses the crucial importance of the digital terrain model used as the basis for shading as well as the proper generalization of the relief. Experiments with shading modules of ArcGIS and Surfer, aiming to explore the functionality of algorithms they employ, have demonstrated significant similarity of the results. In conclusion, the authors attempt to answer the question posted in the title of the article. In their view, analytical shading is not art because shading algorithms are incapable of producing the visually beautiful effects that an experienced cartographer with artistic talents can create.

scholarly journals RESEARCH OF TECHNICAL CHARACTERISTICS OF NEW TYPES OF COUPLINGS

2020 ◽  
pp. 113-121
Author(s):  
Oleksii Tokarchuk ◽  
Yurii Polievoda
Keyword(s):  
Elastic Element ◽  
Rational Design ◽  
Experimental Studies ◽  
Bending Moment ◽  
Operational Reliability ◽  
Modern Technology ◽  
Operating Conditions ◽  
The Moment ◽  
Working Bodies ◽  
Moment Of Resistance

Dynamic loads that occur during the operation of existing couplings cause significant shock loads, which leads to rapid wear of the surfaces of the couplings and shortens the service life. Modern technology faces the task of improving the operational reliability of the working bodies and drives of machines. One way to solve this problem is to develop and use high-precision and low-dynamic safety couplings. In this regard, the question of developing new designs of safety couplings that reduce impact loads and increase the reliability and durability of machinery is relevant. The synthesis of structural and kinematic schemes of ball, cam and planetary safety couplings, the method of their calculation in combination with the nature of the change in the moment of resistance on the working body of the equipment. The article conducts a set of theoretical and experimental studies to determine their rational design, kinematic and dynamic parameters that will satisfy the operating conditions of machines and mechanisms. A force analysis of the elastic element (ring spring) was performed. The scheme of loading of an elastic element by two forces and other settlement schemes are constructed, namely: equivalent system; force diagrams for determining the load torque; force schemes for determining the unit moment; schemes of total bending moment; force schemes to determine the total unit moment. During static experimental studies of the developed ball safety couplings, the nature of their operation was established, the maximum torque at the two stages of operation of the couplings was determined and a comparative analysis between the results of theoretical and experimental studies was performed. The positive results of experimental researches of the developed coupling and theoretical positions which can be applied to a substantiation and a choice of rational parameters of the developed designs of couplings and their engineering designing were confirmed.

Sign in / Sign up

Export Citation Format

Share Document