scholarly journals Research of mobile combined feed preparation unit

2020 ◽  
Vol 11 (4) ◽  
pp. 33-39
Author(s):  
V. S. Khmelovskyi ◽  

The issues of implementation of the technological process of preparation of feed components for feeding for cattle are considered. The main factors of complete feeding are: a complete set of essential nutrients, timely and affordable and optimally coordinated in quantitative terms of their entry into the bodies of animals. The process of grinding feed components, to a large extent, depends on their physical and mechanical properties. One of the conditions for preparing the feed mixture is the minimum use of additional machines that perform the operations of grinding, mixing and distribution of the finished feed mixture, because it leads to higher energy and labor costs. These costs are associated with additional loading and unloading operations of feed components. In the study of the processes of grinding feed materials, according to the technology of preparation of feed for feeding, using mobile combined feed preparation units, provided their grinding, loading feed components was carried out in the following sequence: first loaded roughage, then root crops, for storage stands out. However, experiments have shown that roughage, in the process of grinding, act as a shock absorber, mitigating the impact loads on the roots of tubers from the knives, cuttings and walls of the hopper. At the first loading of root tubers the process of crushing was more intensive. Experiments with long-fiber materials and roots, showed that the presence of crushed roots in the hopper, when loading roughage, the duration of grinding of the latter does not affect. To intensify the process of grinding long-fiber materials (straw), experiments were conducted with the addition of feed with a larger bulk density (silage), which was introduced after the destruction of the roll. The results of research have shown that the addition of silage can increase the intensity and degree of grinding of straw, this is due to the compaction of the mass in the active cutting zone. This solution allows you to reduce the technological time of the unit and increase its productivity.

2020 ◽  
Vol 2020 (3) ◽  
pp. 24-31
Author(s):  
Z Galimova ◽  
◽  
H Babakhanova ◽  
M Abdunazarov ◽  
I Ismoilov ◽  
...  

Both raw and recycled fiber materials are used for paper production. The increase in percentage use of the latter is due to their paper-forming properties, availability and low cost. The article explores the possibility of using pulp from the inner layer of mulberry twig bark. Mulberry twigs, after removing leaves, which are the main raw material in silk production, have no practical industrial application. Recycling waste - mulberry branches - for the production of pulp is therefore relevant as it is aimed at solving raw material and environmental problems. The purpose of this work is to use local raw materials for paper production, study the impact of processing method of the grinding process on paper forming properties. During grinding the mechanical processes of changes of fibers determine mainly structure of a paper sheet, and colloidal-physical processes - bind and ability of fibers to form strong, homogenous and smooth structure of paper. The structure of the sheet of paper facilitates excessive or "selective" ink absorption into the pores of the paper and thus predetermines the quality of reproduction during the printing process. Methods for determining the physical and mechanical properties of papers were used in this work, and changes in the surface structure of samples cast at various technological modes of the milling process were studied. The results of the study revealed that the addition of cellulose mass from the inner layer of mulberry twig bark helps to obtain a strong paper. The optical properties of the paper, which contains cotton and cellulose from the inner layer of mulberry branch bark, are explained by the whiteness of the added fibers themselves. The strength properties of the paper at a weight grinding degree of 300 CWR are explained by the bond between the split and strongly interwoven fibers of the cellulose fibers. It has been established that the addition of more than 30% cellulose from the inner layer of the mulberry branch bark to the paper pulp mass is undesirable, as this adversely affects the whiteness of the paper


Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 779
Author(s):  
Mohamed Gomah ◽  
Guichen Li ◽  
Salah Bader ◽  
Mohamed Elkarmoty ◽  
Mohamed Ismael

The awareness of the impact of high temperatures on rock properties is essential to the design of deep geotechnical applications. The purpose of this research is to assess the influence of heating and cooling treatments on the physical and mechanical properties of Egyptian granodiorite as a degrading factor. The samples were heated to various temperatures (200, 400, 600, and 800 °C) and then cooled at different rates, either slowly cooled in the oven and air or quickly cooled in water. The porosity, water absorption, P-wave velocity, tensile strength, failure mode, and associated microstructural alterations due to thermal effect have been studied. The study revealed that the granodiorite has a slight drop in tensile strength, up to 400 °C, for slow cooling routes and that most of the physical attributes are comparable to natural rock. Despite this, granodiorite thermal deterioration is substantially higher for quick cooling than for slow cooling. Between 400:600 °C is ‘the transitional stage’, where the physical and mechanical characteristics degraded exponentially for all cooling pathways. Independent of the cooling method, the granodiorite showed a ductile failure mode associated with reduced peak tensile strengths. Additionally, the microstructure altered from predominantly intergranular cracking to more trans-granular cracking at 600 °C. The integrity of the granodiorite structure was compromised at 800 °C, the physical parameters deteriorated, and the rock tensile strength was negligible. In this research, the temperatures of 400, 600, and 800 °C were remarked to be typical of three divergent phases of granodiorite mechanical and physical properties evolution. Furthermore, 400 °C could be considered as the threshold limit for Egyptian granodiorite physical and mechanical properties for typical thermal underground applications.


2021 ◽  
Vol 5 (2) ◽  
pp. 42
Author(s):  
Abdelkrem Eltaggaz ◽  
Ibrahim Nouzil ◽  
Ibrahim Deiab

Minimum Quantity Lubrication nanofluid (MQL-nanofluid) is a viable sustainable alternative to conventional flood cooling and provides very good cooling and lubrication in the machining of difficult to cut materials such as titanium and Inconel. The cutting action provides very difficult conditions for the coolant to access the cutting zone and the level of difficulty increases with higher cutting speeds. Furthermore, high compressive stresses, strain hardening and high chemical activity results in the formation of a ‘seizure zone’ at the tool-chip interface. In this work, the impact of MQL-nanofluid at the seizure zone and the corresponding effects on tool wear, surface finish, and power consumption during machining of Ti-6Al-4V was investigated. Aluminum Oxide (Al2O3) nanoparticles were selected to use as nano-additives at different weight fraction concentrations (0, 2, and 4 wt.%). It was observed that under pure MQL strategy there was significant material adhesion on the rake face of the tool while the adhesion was reduced in the presence of MQL-nanofluid at the tool-chip interface, thus indicating a reduction in the tool chip contact length (TCCL) and reduced seizure effect. Furthermore, the flank wear varied from 0.162 to 0.561 mm and the average surface roughness (Ra) varied from 0.512 to 2.81 µm. The results indicate that the nanoparticle concentration and the reduction in the seizure zone positively influence the tool life and quality of surface finish.


2012 ◽  
Vol 13 (3) ◽  
pp. 352-361 ◽  
Author(s):  
Florian Baumann ◽  
Tim Friehe

AbstractThis paper analyzes the effects of regulatory uncertainty regarding labor costs on investment in a liberalized market. We distinguish between the external investment margin (market entry) and the internal investment margin (technology), and establish that regulatory uncertainty affects these margins differently, encouraging market entry, but discouraging technological investment. As a consequence, the impact of regulatory uncertainty on competition in liberalized markets is a combination of these two countervailing forces.


2018 ◽  
Vol 13 (6) ◽  
pp. 1475-1501 ◽  
Author(s):  
Varaporn Pangboonyanon ◽  
Kiattichai Kalasin

Purpose The purpose of this paper is to investigate how within-industry diversification affects the financial performance of small- and medium-sized enterprises (SMEs) in emerging markets (EMs). The authors draw on both the resource-based view and the institutional perspective and argue that within-industry diversification can enhance the financial performance of SMEs in EMs. Due to institutional voids in emerging economies, SMEs can gain additional benefits from scope economies, as well as from market returns, by filling product market voids and gaps in business ecosystems, while also enjoying low input and labor costs that reduce the coordination costs of diversification. This, in turn, enhances benefits of within-industry diversification, thereby resulting in higher financial profitability. Design/methodology/approach This study employs panel data econometrics to estimate the model. The authors test hypotheses on 195 firms, originating from five countries in Southeast Asia, during the period of 2009–2014. Findings The empirical results support the arguments. Within-industry diversification has a positive impact on the performance of SMEs in EMs. These effects become weaker when the institutional contexts are more developed. Nevertheless, such effects become stronger when SMEs in EMs are more efficient. Research limitations/implications The relationship between within-industry diversification and performance is a positive linear pattern, which differs from the pattern in advanced economies. In addition to unrelated diversification, the related diversification is preferable for firms in EMs. Practical implications The paper provides implications for SMEs that aim to enhance their performance by engaging in single product lines and within-industry diversification. Originality/value This paper examines the different ways within-industry diversification can enhance SMEs performance in EM contexts.


2008 ◽  
Vol 19 (4) ◽  
pp. 348-353 ◽  
Author(s):  
Rafael Leonardo Xediek Consant ◽  
Erica Brenoe Vieira ◽  
Marcelo Ferraz Mesquita ◽  
Wilson Batista Mendes ◽  
João Neudenir Arioli-Filho

This study evaluated the effect of microwave energy on the hardness, impact strength and flexural strength of the Clássico, Onda-Cryl and QC-20 acrylic resins. Aluminum die were embedded in metallic or plastic flasks with type III dental stone, in accordance with the traditional packing technique. A mixing powder/liquid ratio was used according to the manufacturer's instructions. After polymerization in water batch at 74ºC for 9 h, boiling water for 20 min or microwave energy at 900 W for 10 min, the specimens were deflasked after flask cooling at room temperature, and submitted to finishing. Specimens non-disinfected and disinfected by microwave irradiation were submitted to hardness, impact and flexural strength tests. Each specimen was immersed in distilled water and disinfected in a microwave oven calibrated to 650 W for 3 min. Knoop hardness test was performed with 25 g load for 10 s, impact test was carried out using the Charpy system with 40 kpcm, and 3-point bending test with a crosshead speed of 0.5 mm/min until fracture. Data were submitted to statistical analysis by ANOVA and Tukey's test (?=0.05). Disinfection by microwave energy decreased the hardness of Clássico and Onda-Cryl acrylic resins, but no effect was observed on the impact and flexural strength of all tested resins.


2018 ◽  
Vol 10 (7) ◽  
pp. 2465
Author(s):  
Laura Brad ◽  
Gabriel Popescu ◽  
Alina Zaharia ◽  
Maria Claudia Diaconeasa ◽  
Daniela Mihai

The importance of agricultural financing in ensuring food security and safety, jobs, poverty reduction, economic growth and more recently, climate change mitigation, natural resource conservation and sustainable development imposes periodic analysis of the factors which might influence the farmers’ financial situation, in order to improve it. One way of assessing this is to analyze the agricultural debt. In this context, based on previous models, the paper aims to assess the impact of specific factors on the agricultural debt level in the European Union during 2008–2015, as these should be considered in future common agriculture policies as well as in achieving sustainable agriculture. The research was conducted based on econometric techniques, by applying panel models in the Eviews 7.0 software-64 bit version. More than 20 variables were considered in the analysis. Some of the findings suggest that an increase in subsidies as well as the share of cash flow in the total existing capital would determine considerable reductions of the total debt. Decoupled subsidies seem to have a higher impact than coupled subsidies on short term debt, while its value is between the one found for coupled subsidies in the case of long term debt. Large farms/companies, to which decoupled payments are granted, have higher debts on long run and on total debt. The same units, to which coupled subsidies were granted, have smaller short-term debt. In contrast, the increases of labor costs, fixed costs, and crop/livestock costs lead to an increase in the total debt, since the farms require additional financial resources to cover the expanded costs. Also, the results suggest that short-term debts are mainly formed of long-term loans that reached maturity. In this case, the authors support the idea of differentiated financing programs for the agricultural activities because of their peculiarities and reinforced by the need to turn the intensive agriculture into a sustainable and plentiful one.


2020 ◽  
pp. 451-457
Author(s):  
Aleksandr Yur'yevich Vititnev ◽  
Yuriy Davydovich Alashkevich ◽  
Natal'ya Geral'dovna Chistova ◽  
Roman Aleksandrovich Marchenko ◽  
Venera Nurullovna Matygullina

This paper presents the results of experimental studies of the physical and mechanical properties of wood-fiber boards of the wet production method when regulating the design and technological parameters of the grinding process. This allowed us to determine the influence of the working clearance between the grinding discs and the concentration of fibre mass with the subject to of quality change wood fiber after defibrator using the developed construction of the disc fibrillation action on the physico-mechanical properties of boards. As a result of the experiment, regression models were obtained that adequately describe the studied grinding process and allow predicting the values of physical and mechanical properties of the finished product depending on the established  parameters process. A comparative analysis of the size and quality characteristics of the fiber semi-finished product and its fractional composition when using a developed construction the disc of refiner fibrillation action and a traditional design used in industry is carried out. The preferential efficiency of the grinding process under the fibrillating effect the disc of refiner in comparison with the traditional construction disc of refiner is established. As a result, there is a significant improvement in the quality indicators of the fiber semi-finished product and its composition due to the formation and predominance in the total mass of long and thin, respectively, flexible fibrillated fibers with high tile-forming properties, which allows to increase the strength properties of the product (by 20–25%), without using binding resins.


2010 ◽  
Vol 2 (1) ◽  
pp. 69-103 ◽  
Author(s):  
J. Klokočník ◽  
J. Kostelecký ◽  
I. Pešek ◽  
P. Novák ◽  
C. A. Wagner ◽  
...  

Abstract. In 2008 the new Earth Gravitational Model (EGM08) was released. It contains a complete set of spherical harmonic coefficients of the Earth's gravitational potential (Stokes parameters) to degree 2190 and order 2159 that can be used for evaluation of various potential quantities with both the unprecedented accuracy and high spatial resolution. Two such quantities, the gravity anomaly and second-order radial derivative of the disturbing potential, were computed over selected areas with known impact craters. The displays of these derivatives for two such sites clearly show not only the strong circular-like features known to be associated with them but also other symmetrical structures which appear to make them multiple impact sites. At Popigai, Siberia, the secondary circular features fall in a line from the primary in the SE direction. At Chicxulub, Yucatán, there appears to be one secondary crater close to the primary in the NE direction, as well as possibly others in the vicinity of the main crater. Gravity information alone is not proof of the impact craters but it is useful in identifying candidate sites for further study, for future examination by geologists and geophysicists.


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