Influence Of Various Technological Parameters Research Articles

Epoxidation of cyclohexene with cyclohexyl hydroperoxide

Objectives. To investigate the regularities of the process of joint production of epoxycyclohexane, cyclohexanol, and cyclohexanone using the cyclohexene epoxidation reaction with cyclohexyl hydroperoxide in the presence of an ammonium paramolybdate catalyst, representing an alternative to the method of cyclohexanol and cyclohexanone synthesis by alkaline catalytic decomposition of cyclohexyl hydroperoxide.Methods. The qualitative and quantitative analysis of the obtained intermediate and target compounds was determined using modern physicochemical research methods: gas–liquid chromatography using the Chromatec-Crystal 5000.2 hardware and software complex with a flame ionization detector and infrared spectroscopy on an RX-1 infrared Fourier spectrometer. The content of hydroperoxide in the oxidation products was determined using iodometric titration, while the carboxylic acid content was determined by the titrimetric method based on the neutralization reaction.Results. The presented method for obtaining cyclohexanol and cyclohexanone together with epoxycyclohexane by the reaction of cyclohexene epoxidation with cyclohexyl hydroperoxide containing cyclohexane in the products of high-temperature liquid-phase oxidation is experimentally substantiated. The influence of various technological parameters on the process of liquid-phase oxidation of cyclohexane to hydroperoxide is described. The conditions for carrying out this reaction are determined to ensure the achievement of a content of cyclohexyl hydroperoxide of 1.5 wt % in the products of oxidation. The regularities of the epoxidation reaction of the synthesized cyclohexyl hydroperoxide with cyclohexene in the presence of an ammonium paramolybdate catalyst are analyzed.Conclusions. Epoxidation of cyclohexene with cyclohexyl hydroperoxide produced epoxycyclohexane at a yield of 80–90% and a conversion of cyclohexane hydroperoxide of 85%.

Study of the influence on potassium chloride enrichment technology in potassium ore

Due to the fact that the rich reserves of potash minerals are decreasing in the world, scientific research is being carried out on the development of effective technologies for beneficiation of minerals containing a small amount of potassium. In this regard, to study the mineralogical composition of low-grade potassium ores of the Tyubetagan mine, to conduct theoretical analysis of the galurgic method of beneficiation and to carry out research in laboratory conditions, to study the influence of various technological parameters on product output and to find optimal conditions, to develop a technological scheme of beneficiation of low-grade sylvinite ores by the galurgic method special attention is paid to the output. In this study, the mineralogical composition of potash ores of Tubegatan mine was studied and methods of beneficiation were proposed according to the relationship between the content of KCl, NaCl, insoluble residue and particle size of potash ores.

The effect of temperature on the decomposition process of propane-butane mixture at high temperatures

In the work, the composition of the starting materials and reaction products was checked by the chromatographic method. The purpose of the work is to study the effect of temperature on the decomposition process of the propane-butane mixture at high temperatures. Qualitative analysis was carried out by the method of "witnesses", and quantitative analysis was carried out by the method of internal normalization. Spatial composition analysis was performed on a DRON- 4.0 (CuKa - radiation) diffractometer, particle size scanning electron microscopy ((JSM-6380 LV) Scanning Electron (Micscope) and emission electron microscopy (EMV-100BR)). The relative surface area was determined by the BET method. The total pore volume was calculated from the amount of nitrogen adsorbed at peak saturation. Pore size distribution was determined by the BJH (Barrett-Joyner-Halendr) method. The effect of temperature and exposure time on the decomposition of the propane-butane mixture at high temperatures was carried out under the following optimal conditions: the study of the effect of temperature on the yield of products was carried out with an exposure time of 0.12 seconds and a water vapour: reagent ratio of 0.4:1 and a temperature range of 700- 900 ℃. The influence of various technological parameters on the process of decomposition of the propane-butane mixture under the influence of temperature in an airless place at high temperature was studied. The increase in temperature and the decrease in the time of the initial substance (reagent) in the reaction zone allows for increasing the output of ethylene from the propane-butane mixture, in which the optimum temperature for the production of lower molecular unsaturated hydrocarbons, i.e. ethylene, propylene and butylene, is 850 ℃. The catalyst created for the decomposition of a propane-butane mixture containing 5%CrF3*CoF2*5%NiF2*2%ZrO2*8%Na2SO4 at high temperatures has been shown to exhibit high activity and selectivity in the catalytic decomposition of propane-butane mixtures.

Belite Sludges from Coal-fired Power Plant Ash

The results of experimental studies aimed at developing a technology for producing belite sludge from high-alumina ash of coal-fired power plants are presented. The influence of various technological parameters on the process of obtaining the target product has been studied. The possibility of obtaining two grades of belite sludge is shown by the example of the ashes of thermal power plants in the Ural region.

Orthogonal optimization for effective classification of different tea leaves by a novel pressure stabilized inclined chamber classifier

AbstractIn the field of tea separation and processing, modern high‐tech can realize the nondestructive separation of tea and improve the quality of tea. In this study, a novel pressure‐stabilizing inclined chamber classifier was proposed, which was used to adjust the particle size distribution of tea at the entrance of the classifier. A suitable cavity can control the change of wind speed so that tea leaves are not easy to bend and deform, and the success rate of grading is improved. Second, three parameters that affect the success rate of tea classification are put forward: suction wind speed V, suction distance H, and suction distance L. When the parameters are V = 6 m/s, H = 40 mm, and L = 20 mm, the best response value is obtained, thus the most suitable entrance shape is obtained. Finally, the internal flow field of the classifier is analyzed, and different sizes of tea leaves are classified according to the change of air pressure flowing through the closed structure cavity. With the distribution of air velocity, tea leaves fall into collectors with different widths. Therefore, the flow field simulation test shows that the classifier can classify high‐quality tea according to the airflow. The model lays a foundation for further study of the fluid–solid coupling process and interaction between particles.Practical ApplicationsIn this study, a novel pressure‐stabilized inclined chamber classifier was designed, and three parameters that affect the success rate of tea classification were put forward. The process conditions were optimized by orthogonal tests, and the number of experiments was reduced. This method can be used to evaluate the influence of various technological parameters on tea classification. In order to improve the classification success rate, it is necessary to statistically discuss the results of the orthogonal test and flow field analysis.

The influence of technological methods for the production of ripening cheeses on the development and metabolism of the acid-forming component of the bacterial starter culture of Lactococcus lactis subsp. cremoris.

Cheese is a food product obtained by concentration and biotransformation of the main components of milk under the influence of enzymes of microorganisms and physicochemical factors. The article presents the results of the influence of various technological parameters of the production of ripening cheeses on the course of microbiological and biochemical processes under the influence of starter microorganisms of Lactococcus lactis subsp. cremoris. As part of the research, Gouda-type cheeses with a fat mass fraction of 45 % were produced using a combination of Lactococcus lactis subsp. cremoris. The degree of influence of the temperature of the second heating, salt content and ripening conditions on the course of physicochemical, biochemical and organoleptic processes and quality indicators of cheese, determined by the level of development and metabolism of the used starter cultures, was evaluated. The best result was obtained with a combination of the temperature of the second heating (38±0.5) °C, the salt concentration in the finished product (2.8±0.1) % and the ripening temperature (11±1) °C, which provided conditions for the directed development and metabolism of starter microorganisms of Lactococcus lactis subsp. cremoris.

Device modelling of non-fullerene organic solar cell with inorganic CuI hole transport layer using SCAPS 1-D

Hole transport layer (HTL) plays a significant role in the device performance of organic solar cells. PEDOT:PSS, the most commonly used HTL degrades the device and effects the stability of Organic solar cell (OSC). An alternate material to maximise the output of OSC is necessary. In this paper, a complete simulation study on the performance of (PBDB-T) poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b]dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5-c]dithiophene-4,8-dione)]/(ITIC)3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone)-5,5,11,11-tetraki(4-hexylphenyl)-dithieno[2,3-d:2,3-d]-s-indaceno [1,2-b:5,6-b]dithiophene) non-fullerene acceptor (NFA) OSC incorporated with Copper iodide (CuI) as HTL is done using the software SCAPS 1-D. Device modelling is done to study the influence of various technological parameters on the solar cell output. CuI is wider bandgap p-type semiconductor with high stability and available at low cost. The simulation results show that NFA-OSC with CuI as the HTL delivers better efficiency than the conventional structure. Upon optimization, the device output shows Power conversion efficiency (PCE) of 15.68%, Fill Factor (FF) of 79.59%, Short Circuit Current density (Jsc) of 20.1525 mA/cm2 and Open Circuit Voltage (Voc) of 0.9773 V. The values are encouraging to develop NFA-OSC with CuI as the hole transport layer in the near future.

Investigation of obtaining low-sulfur coke from heavy oil residues in the presence of a recycling agent

The current state of the oil refining industry requires obtaining high-quality products that meet environmental requirements. An important issue is the deep processing of oil, as well as the use of oil waste as a raw material. The paper is devoted to study of the influence of various technological parameters during delayed coking of tar on the yield and physicochemical properties of hydrocarbon fuel components and solid-phase product - petroleum coke. As raw materials tar obtained from the Kumkol deposit (Kazakhstan) was applied. Heavy oil residues were coked at a temperature of 510 °C and an overpressure of 0.5 MPa in a laboratory coking unit. It was found that the group hydrocarbon composition of gasoline fraction is consisting mainly from isoparaffin (22.04%) and naphtenic compounds (22.15%), kerosene fraction from paraffin (19.42%) and isoparaffin (25.79%) and diesel fraction composition comprise paraffin (26.04). Raman scattering at 1165 cm−1 belong to CC aromatic and C = C region and indicates a high crystallinity of the coke structure. Coke is obtained with more developed specific surface 6.76 m2/g. The volume of the liquid product is 12.06 g (60.3%) and gas evolution amounted 5%.

Analysis of Mechanical Factors at Deep Cultivation

Background. During the passage of technological processes, microorganisms are prone to the influence of various technological parameters, such as changes in temperature, pH of the culture medium, chemical, biological, and mechanical influences. To date, the degree of study of these effects is different. One is almost fully covered, while others are practically not studied at all. In some cases, the study of one factor leads to the emergence of new tasks and nuances in the study of others, since they are all inextricably interconnected. One of the least studied, but the most critical are mechanical effects. It has been unequivocally established that the rotation speed and the design of the mixing device affect the final product yield, but the nature and mechanisms of this effect remain unknown. Objective. The aim of the paper is to find out the effects of mechanical factors on microorganisms in the process of deep cultivation, in particular on recombinant bacteria and micelles, since they are the most sensitive to these factors, using literary data. And, on this basis, tasks for further research should be formulate. Methods. The research of scientists from different countries on the effects of the mechanical effects of mixing on microorganisms in the process of deep cultivation is studied and analyzed. Results. According to the literature data, dependencies of stirring rate on growth and microorganism status have been established, and recommendations for optimal mixer speeds for specific types of bacteria and micelles, which require further experimental confirmation, are provided. It has been found that increasing the size of cells increases their sensitivity to mechanical influences. The analysis of litera­ture has shown that viscosity decreases with increasing mixing intensity, which imposes a certain imprint on the kinetics of the process. It was detected that in conditions of deep cultivation with mechanical mixing the mycelial fungi, in contrast to bacterial organisms, is divided into relatively small segments that retain the ability to reproduce and accumulate biomass. Conclusions. The analysis of literature data showed that the mycelial fungi are the most sensitive to mechanical factors during deep cultivation. The optimum mixing speed for them is 120–150 rpm. It is necessary to modernize the design of the mixing device to optimize this process, to ensure the supply of nutrients and oxygen to all cells during deep cultivation in sufficient quantity for their development.

DIFFERENT TYPES OF FILLERS IN FINE-GRAINED CONCRETE MADE FROM INDUSTRIAL WASTE WITH BINDING MATERIAL

The work is dedicated to the development of nano-structured paints with a barrier effect. The process of the preparation of such compositions has been studied. The influence of various technological parameters on the processing of these compositions is shown. A practical and effective method for monitoring the progress of this process is proposed. The contribution of technological parameters that allow scaling of the obtained results to experimental and industrial technological lines equipped with serial equipment for the production of paint and varnish composite materials for various purposes is estimated, namely, the dependence of the processing efficiency of carbon nanotubes in the solution medium of an epoxy oligomer on the angular velocity is established. In addition, the temperature limits for the processing of these nanotubes are established for the preparation of nano-structured paint and varnish compositions, which have a barrier effect. It has been established that for the intensification of the processing process, it is necessary to use dispersing bodies and assess the effect of their geometric parameters together with the degree of filling on the efficiency of this processing process. On the basis of this research, the mathematical expression connecting volume capacity with various technological parameters for an estimation of efficiency of process of manufacture of the nano-structured paint and varnish compositions possessing barrier effect is offered.

Technique Influence on Cast-Iron Surface Textures Induced by LST

The influence of various technological parameters on laser-textured cast-iron surface is presented in this paper. A kind of micro-pits array was analyzed using single-factor method, where Nd3+: YAG solid laser is applied to obtained regular surface textures, and 3D surface morphology profiler used to compare the surface topographies related to technology. Among of the set of parameters, the distance between working surface and cavity mirror, pumping current and number of pulses were concerned variables in the process of manufacturing of microstructures. The geometry structures for variables were characterized by the radius and depth of micro-pits. Moreover, surface roughness for different technological parameter were expressed with Ra, Rq and Rt. Abbott curve was adopted for valuing the abrasion resistance of given textured surfaces. One optical range of parameters is achieved for improving the level of laser texturing surface.

Growth of large KDP single crystals for UV spectrum range

The influence of various technological parameters of crystallization (acidity of growth solutions, crystallization temperature, growth rate, degree of solution purification) on the optical absorption of large KDP single crystals has been studied in the UV range of the spectrum. It is shown that the method of solvent recirculation with the use of the starting material with the microimpurity content not exceeding 5 × 10−5 wt % and solution ultrafiltration under the optimum crystallization conditions (tcr = 80°C, Vcr ∼ (0.8–1.6) × 10−6 cm/s, pH 4) enables one to grow KDP single crystals with cross sections up to 300 × 300 mm2 and the transmission in the vicinity of the fundamental absorption edge λ = 200 nm) equal to 86%.

Forming a solid substitution solution in niobium and tantalum

The influence of various technological parameters (temperature, exposure, concentration of diffusion element) on the process of molybdenizing of niobium and tantalum was studied. A mechanism of forming (β- and α-solid substitution solution in refractory metals has been offered.

RESOURCE-SAVING TECHNOLOGY FOR GERMINATING SOY BEANS

The article describes the relevance of using soybean sprouts in the nutrition of the population, and, consequently, the feasibility of developing resource-saving technologies for sprouting soybeans. The influence of various technological parameters (temperature, humidity, convection) on the rate of germination of soybeans in a steam convection apparatus has been determined; the organoleptic indicators of the quality of sprouts were evaluated for various parameters of germination. An rational technology has been developed for germinating dry soybeans to sprouts 5 cm long. The possibility of extending the shelf life of the obtained soybeans by means of intensive cooling and vacuum packaging has been studied; the storage period is set. The nutritional value of the resulting product was assessed.

Electrical methods for optimization of ceramics processing technology

Suitable electrical and dielectrical parameters reflect structural changes in test materials and aid in the determination of the influence of various technological parameters. The temperature dependence is described of both direct conductiviity and electrical modulus for optimal composition assessment and processing technology in ZrO 2 ceramics, with ingredients, basalt and special glasses. The technological variable during ceramics processing (e.g. pressing pressure and controlled sintering) substantially affect structure and properties. These methods are used to establish the influence of the various ingredients and their concentrations, leading to better mechanical and technological properties. The aim is to improve our fundamental knowledge about ceramics where commercial aspects demand optimum processing and manufacturing technology. The tests are also suitable for the assessment of phase transformations, recrystallization, etc., and the detection of their mechanisms.

Model for the axial growth of filamentary silicon crystals

We propose a model for the axial growth of filamentary silicon crystals, based on the assumption that the crystallization occurs in a diffusion-limited regime. A kinetic equation is obtained which enables us to analyze changes in the crystal growth rate under the influence of various technological parameters.

Effect of Technological Parameters on Electrophoretic Detection of Cow's Milk in Ewe's Milk Cheeses

Electrophoretic analysis of whey proteins was used to determine the presence and amount of cow's milk in ewe's milk cheeses. Various combinations of types of whey proteins were compared; using the ratio of cow's β-lactoglobulin A and B to bovine serum albumin was most accurate. The influence of various technological parameters was studied. Vegetable rennet exerted greater proteolytic action on whey proteins than did animal rennet but did not influence the level of detection. Type of pressing had no effect, There was no influence of aging on the level of detection in either Manchego cheese or Roquefort cheese. When silver nitrate was used for staining, quantities of cow's milk at levels of 1% or more were detectable in various types of cheese. Heating of the cow's milk to 90°C for 30min denatured the whey proteins and gave negative results when cow's milk was added to sheep's milk for cheese making. This method has the advantage that whey proteins are less susceptible to proteolysis than caseins and is a simple procedure and of low cost.

The submicron inverted MODFET I-GaAs/N +-AlGaAs: a 2D Monte-Carlo study

A two-dimensional Monte-Carlo simulation of an inverted MODFET structure I-GaAs/N +-AlGaAs has been performed. The influence of various technological parameters have been studied such as the GaAs undoped layer thickness, the AlGaAs layer thickness, doping level and aluminum composition, the gate length or the temperature. The results show that higher transconductance and cut-off frequency values should be obtained as compared to conventional MODFET structures.

Preparation of InN epitaxial layers in InCl3NH3 system

AbstractThe epitaxial growth of InN by the open tube flow method using the interaction of InCl3 and NH3 is discussed. The influence of various technological parameters on the process and structure perfection of the epitaxial layers, grown on the single crystal (0001)‐oriented sapphire substrates is considered. The main kinetic dependences of the process are plotted and discussed.InN epitaxial layers were mosaic and n‐type with electron concentration 2 · 1020–8 · 1021 cm−3 and mobilities 50‐35 cm2/V · s, respectively.

L'effet des dislocations cristallines sur le bruit en creneaux des transistors bipolaires au silicium

We are studying the correlation between the rate of crystalline dislocation at the surface of various transistor wafers and the percentage of transistors presenting burst noise; we show that there is proportionality between these two quantities. Also, we are clarifying the influence of various technological parameters of manufacture (heating, doping) on dislocations and burst noise.