scholarly journals Substantiation of rational parameters of the sensitive element of the grain moisture indicator

2020 ◽  
pp. 77-81
Author(s):  
V. G. Mironenko ◽  
A.M. Boris ◽  
N. V. Tyutyunnik
Keyword(s):  
Regression Model ◽  
Sensitive Element ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Sensing Element ◽  
Capacitor Plate ◽  
Electric Capacitance ◽  
Information Tools ◽  
Grain Moisture ◽  
Microsoft Office

Annotation Purpose. Improving the efficiency of harvesting work based on the development of information tools for determining grain moisture. Methods. Method of regression analysis, method of planning and processing of experimental data using software packages – “Microsoft Office Excel 2010”, Microsoft Visual Studio Community 2015 in C ++, statistical method of processing research results. Results. Regression model of the dependence of the electric capacitance of the capacitor on the working area of the plates of the capacitor of the sensing element and the distance between the plates of the capacitor. Rational values of the parameters of the sensitive element of the grain moisture indicator. Conclusions 1. The NSC “IAEE” has developed a simple and reliable indicator of grain moisture, the principle of which is based on the change in dielectric constant between the plates of the capacitor. 2. A regression model of the dependence of the electric capacitance of the capacitor on the working area of the capacitor plates of the sensing element and the distance between the plates of the capacitor, which allowed to determine that at a capacitor plate area of 200 mm, the rational value of the distance between capacitor plates is 0.69 mm. 3. The values of the rational values of the distance between the plates of the capacitor of the sensitive element of the grain moisture indicator, which are obtained in theoretical calculations and experimental studies, differ by 15%. Keywords: grain, humidity, grain moisture indicator, primary converter, rational parameters.

Theoretical and experimental studies of palladium-catalyzed site-selective C(sp3)−H bond functionalization enabled by transient ligands

2017 ◽  
Author(s):  
Haibo Ge ◽  
Lei Pan ◽  
Piaoping Tang ◽  
Ke Yang ◽  
Mian Wang ◽  
...  
Keyword(s):  
Bond Activation ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Bond Functionalization ◽  
Aliphatic Ketones ◽  
Site Selectivity ◽  
Mechanistic Investigation ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Site Selective

Transition metal-catalyzed selective C–H bond functionalization enabled by transient ligands has become an extremely attractive topic due to its economical and greener characteristics. However, catalytic pathways of this reaction process on unactivated sp<sup>3</sup> carbons of reactants have not been well studied yet. Herein, detailed mechanistic investigation on Pd-catalyzed C(sp<sup>3</sup>)–H bond activation with amino acids as transient ligands has been systematically conducted. The theoretical calculations showed that higher angle distortion of C(sp2)-H bond over C(sp3)-H bond and stronger nucleophilicity of benzylic anion over its aromatic counterpart, leading to higher reactivity of corresponding C(sp<sup>3</sup>)–H bonds; the angle strain of the directing rings of key intermediates determines the site-selectivity of aliphatic ketone substrates; replacement of glycine with β-alanine as the transient ligand can decrease the angle tension of the directing rings. Synthetic experiments have confirmed that β-alanine is indeed a more efficient transient ligand for arylation of β-secondary carbons of linear aliphatic ketones than its glycine counterpart.<br><br>

A New Approach for Predicting the Value of Gene Expression: Two-way Collaborative Filtering

2019 ◽  
Vol 14 (6) ◽  
pp. 480-490 ◽  
Author(s):  
Tuncay Bayrak ◽  
Hasan Oğul
Keyword(s):  
Gene Expression ◽  
Regression Model ◽  
Collaborative Filtering ◽  
High Throughput Sequencing ◽  
Mean Squared Error ◽  
Experimental Studies ◽  
Kernel Functions ◽  
Feature Representation ◽  
Sequencing Analysis ◽  
Computational Systems Biology

Background: Predicting the value of gene expression in a given condition is a challenging topic in computational systems biology. Only a limited number of studies in this area have provided solutions to predict the expression in a particular pattern, whether or not it can be done effectively. However, the value of expression for the measurement is usually needed for further meta-data analysis. Methods: Because the problem is considered as a regression task where a feature representation of the gene under consideration is fed into a trained model to predict a continuous variable that refers to its exact expression level, we introduced a novel feature representation scheme to support work on such a task based on two-way collaborative filtering. At this point, our main argument is that the expressions of other genes in the current condition are as important as the expression of the current gene in other conditions. For regression analysis, linear regression and a recently popularized method, called Relevance Vector Machine (RVM), are used. Pearson and Spearman correlation coefficients and Root Mean Squared Error are used for evaluation. The effects of regression model type, RVM kernel functions, and parameters have been analysed in our study in a gene expression profiling data comprising a set of prostate cancer samples. Results: According to the findings of this study, in addition to promising results from the experimental studies, integrating data from another disease type, such as colon cancer in our case, can significantly improve the prediction performance of the regression model. Conclusion: The results also showed that the performed new feature representation approach and RVM regression model are promising for many machine learning problems in microarray and high throughput sequencing analysis.

scholarly journals PULSE METHOD FOR DETERMINATION OF TIME PARAMETERS THERMAL FIRE DETECTOR

2021 ◽  
Vol 4 (164) ◽  
pp. 166-170
Author(s):  
Ya. Kozak
Keyword(s):  
Electric Current ◽  
Time Constant ◽  
Sensitive Element ◽  
Integral Transformation ◽  
Pulse Method ◽  
Auxiliary Parameter ◽  
Sensing Element ◽  
Fire Detector ◽  
Time Parameters ◽  
Analytical Expressions

For thermal fire detectors with a thermoresistive sensitive element, the method of determining its time parameters is justified. The time parameters of operation and the time constant of the thermal fire detector are considered as time parameters. The method is based on the use of the Joule-Lenz effect, for the implementation of which single pulses of electric current are passed through the thermoresistive sensitive element of the fire detector. Pulses having the shape of a quarter sinusoid or a quarter cosinusoid are used as such test signals. Using the Laplace integral transformation, analytical expressions are obtained, which represent the formalization of the reaction of the thermoresistive sensitive element of the fire detector to the corresponding test signals. These analytical expressions are used to obtain the functional dependences of the fire detector time constants on the pulse duration of the electric current and the auxiliary parameter. The auxiliary parameter is the ratio of the values ​​of the output signal of the thermal fire detector at two fixed points in time. This choice of auxiliary parameter allows to ensure invariance with respect to the transfer coefficient of the thermal fire detector with a thermoresistive sensing element. The fixed moments of time are chosen to be equal to half and three quarters of the duration of the pulses of electric current flowing through the thermoresistive sensitive element of the fire detector. The time of operation of the thermal fire detector is determined in the form of two additive components, one of which is a time constant of the fire detector, and the other is determined by the values ​​of normalized parameters in accordance with existing regulations. A sequence of procedures is given, which together represent a method of determining the time parameters of thermal fire detectors of this type.

Research of stamping of unequal channel bars. Part 5. Methods for calculating the extrusion of channels. 2. Extrusion of non-strengthening material

2021 ◽  
pp. 46-52
Author(s):  
A.L. Vorontsov
Keyword(s):  
Plane Strain ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
High Accuracy ◽  
Experimental Results ◽  
Die Forging

The results of experimental studies on the extrusion of channels from non-strengthening material are presented. Comparison of theoretical calculations with experimental results showed the high accuracy of the derived formulas. Keywords: die forging, extrusion, punch, matrix, misalignment, plane strain. [email protected]

scholarly journals Platinum–copper single atom alloy catalysts with high performance towards glycerol hydrogenolysis

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Xi Zhang ◽  
Guoqing Cui ◽  
Haisong Feng ◽  
Lifang Chen ◽  
Hui Wang ◽  
...  
Keyword(s):  
Active Sites ◽  
High Performance ◽  
Reaction Pathway ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Value Added ◽  
Catalytic Performance ◽  
Single Atom ◽  
Glycerol Hydrogenolysis ◽  
Single Atom Alloy

AbstractSelective hydrogenolysis of biomass-derived glycerol to propanediol is an important reaction to produce high value-added chemicals but remains a big challenge. Herein we report a PtCu single atom alloy (SAA) catalyst with single Pt atom dispersed on Cu nanoclusters, which exhibits dramatically boosted catalytic performance (yield: 98.8%) towards glycerol hydrogenolysis to 1,2-propanediol. Remarkably, the turnover frequency reaches up to 2.6 × 103 molglycerol·molPtCu–SAA−1·h−1, which is to our knowledge the largest value among reported heterogeneous metal catalysts. Both in situ experimental studies and theoretical calculations verify interface sites of PtCu–SAA serve as intrinsic active sites, in which the single Pt atom facilitates the breakage of central C–H bond whilst the terminal C–O bond undergoes dissociation adsorption on adjacent Cu atom. This interfacial synergistic catalysis based on PtCu–SAA changes the reaction pathway with a decreased activation energy, which can be extended to other noble metal alloy systems.

scholarly journals Numerical simulation of the stress-strain state of complex-reinforced elements

2019 ◽  
Vol 13 (2) ◽  
pp. 110-115
Author(s):  
Olena Krantovska ◽  
Mykola Petrov ◽  
Liubov Ksonshkevych ◽  
Matija Orešković ◽  
Sergii Synii ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Strain State ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Theoretical Studies ◽  
Stress Strain ◽  
Narrow Strip ◽  
Stress Strain State ◽  
Graphical Environment ◽  
Experimental And Theoretical Studies

The article describes a developed technique of a numerical simulation of the stress-strain state of complex-reinforced elements, which allows you to create models of double-span continuous. The performed experimental and theoretical studies allowed us to carry out the testing of the developed design model and to justify the reliability of the proposed numerical simulation methodology. The results of the experimental studies were compared with those of the theoretical studies. The theoretical calculus algorithm was developed by using the finite element method. Theoretical calculations were performed by using the mathematical-graphical environment software system LIRA-SOFT and the mathematical and computer program MATLAB. On the basis of the experimental research, the iso-fields of displacements and stresses in the materials of an eccentrically compressed beam with a small bend of the slab were constructed, which collapse behind the inclined narrow strip of concrete and displacements and stresses in the materials of the eccentrically stretched beam, which is destroyed due to the yield of the upper mounting armature.

Graph-Analytical Estimation Method of Natural Ventilation Efficiency during Natural Gas Combustion

2018 ◽  
Vol 931 ◽  
pp. 901-904 ◽  
Author(s):  
Victor I. Chebotarev ◽  
Anastasia P. Pirozhnikova ◽  
Alla V. Koroleva
Keyword(s):  
Natural Gas ◽  
Natural Ventilation ◽  
Theoretical Calculations ◽  
Residential Buildings ◽  
Experimental Studies ◽  
Estimation Method ◽  
Combustion Products ◽  
Gas Combustion ◽  
Analytical Estimation ◽  
Ventilation Duct

Open burning of natural gas when using gas equipment in the premises of residential buildings is considered, taking into account the formation of combustion products, depending on the coefficients of excess air. Theoretical and experimental studies of combustion processes are presented. To determine the aerodynamic process in the ventilation duct, theoretical calculations of the dependence of the discharge at the entrance to the ventilation duct from the outside temperature of the atmospheric air were made. Graph-analytic method of evaluating the effectiveness of natural ventilation is carried out.

scholarly journals Multilayered stable 2D nano-sheets of Ti2NTx MXene: synthesis, characterization, and anticancer activity

2019 ◽  
Vol 17 (1) ◽  
Author(s):  
A. Szuplewska ◽  
A. Rozmysłowska-Wojciechowska ◽  
S. Poźniak ◽  
T. Wojciechowski ◽  
M. Birowska ◽  
...  
Keyword(s):  
Biological Activity ◽  
Mammary Epithelial Cells ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Reactive Oxygen ◽  
Decisive Role ◽  
Max Phase ◽  
Mechanisms Of Toxicity ◽  
Biological Studies

Abstract Background The biological activity of MXenes has been studied for several years because of their potential biomedical applications; however, investigations have so far been limited to 2D titanium carbides. Although monolayered Ti2NTx MXene has been expected to have biological activity, experimental studies revealed significant difficulties due to obstacles to its synthesis, its low stability and its susceptibility to oxidation and decomposition. Results In this paper, we report our theoretical calculations showing the higher likelihood of forming multilayered Ti2NTx structures during the preparation process in comparison to single-layered structures. As a result of our experimental work, we successfully synthesized multilayered Ti2NTx MXene that was suitable for biological studies by the etching of the Ti2AlN MAX phase and further delamination. The biocompatibility of Ti2NTx MXene was evaluated in vitro towards human skin malignant melanoma cells, human immortalized keratinocytes, human breast cancer cells, and normal human mammary epithelial cells. Additionally, the potential mode of action of 2D Ti2NTx was investigated using reactive oxygen tests as well as SEM observations. Our results indicated that multilayered 2D sheets of Ti2NTx showed higher toxicity towards cancerous cell lines in comparison to normal ones. The decrease in cell viabilities was dose-dependent. The generation of reactive oxygen species as well as the internalization of the 2D sheets play a decisive role in the mechanisms of toxicity. Conclusions We have shown that 2D Ti2NTx in the form of multilayered nanoflakes exhibits fair stability and can be used for in vitro studies. These results show promise for its future applications in biotechnology and nanomedicine.

scholarly journals Modeling the mechanical wear of the contact elements of pantograph during high-speed movement

2020 ◽  
Vol 157 ◽  
pp. 01022
Author(s):  
Victor Philippov ◽  
Alexandr Smerdin
Keyword(s):  
Service Life ◽  
High Speed ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Maximum Error ◽  
Life Assessment ◽  
Rolling Stock ◽  
Mechanical Wear ◽  
Wear Process ◽  
Mechanical Component

The use of contact elements with an extended service life is one of the most economical and least costly ways to ensure reliable, economical and environmentally friendly transmission of electricity to rolling stock. To evaluate the service life in OSTU, a methodology for conducting experimental studies of contact pairs of pantograph has been developed and successfully tested, involving bench tests for each pair of contact materials “contact insert - contact wire” in order to determine their optimal combination to reduce wear and increase service life. Assessment of the amount of wear and prediction of the life of the contact elements are made, including using mathematical modeling. The purpose of this article is to improve the mechanical component of the wear model of the contact elements of pantograph in high-speed conditions. The results of experimental studies and theoretical calculations of the mechanical wear of contact elements are presented. The analysis of the graphs allows us to conclude that it is possible to use an improved mathematical model for modeling the mechanical component of the wear process of the elements of contact pairs with a maximum error value of not more than 5%.

Finite Element and Experimental Studies of Creep at the Interface of Press Fitted Gears-Shafts Connections

1996 ◽  
Vol 118 (4) ◽  
pp. 568-572 ◽  
Author(s):  
N. Okamoto ◽  
N. Tanaka ◽  
M. Nogami
Keyword(s):  
Finite Element ◽  
Shear Stress ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Numerical Results ◽  
Frictional Torque ◽  
Slip Model ◽  
Relative Movement ◽  
Stress Variation ◽  
Shrink Fit

It is shown experimentally that relative movement of shrink-fit connections occurs on mating surfaces even if the transmitting torque does not exceed the static frictional torque. However, there is a transmitting torque threshold below which no relative movement occurs. The experimental thresholds agree well with predictions from theoretical calculations of the slip model, which is based on the numerical results of shear stress variation along the interface and on Coulomb’s law of friction.

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