Journal articles on the topic 'Drum mills'
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1
Fistes, Aleksandar, and Gavrilo Tanovic. "The effect of using the drum detachers in the industrial wheat flour mills." Acta Periodica Technologica, no. 44 (2013): 49–56. http://dx.doi.org/10.2298/apt1344049f.
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The work is concerned with the effects of applying the drum detachers as flake disrupters in industrial wheat flour mills. The stocks entering and leaving the drum detachers applied on the different reduction passages in two industrial mills were intercepted and employed in the experiments. The changes in the flour release and flour ash content were followed. The results show that the drum detachers are effective in disrupting the flakes formed in the smooth roller mills grinding zone. However, the contribution of the drum detachers to the overall milling efficiency is in close correlation with the nature of the formed flakes. If the flakes are primarily composed of endosperm particles, the employment of drum detacher results in a statistically significant increase of the flour yields without deterioration of flour quality. If flakes, formed on the end passages of the reduction system, contain large portion of branny particles, the increase of the flour ash content following the drum detacher is statistically significant.
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Meshcheriakov, L., A. Kozhevnykov, and S. Prykhodchenko. "Intellectual agents of targets in analytical constructing of optimum systems of management of drum mills." Collection of Research Papers of the National Mining University 64 (2021): 264–72. http://dx.doi.org/10.33271/crpnmu/64.264.
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Purpose. Justification of the rational use of intellectual agents in forming of the quasi-optimal systems of management furnaces of complexes of type drum mills as observers of complete order. A method of research consists of decision of the best laws management by the mining complexes by the use of methods of the analytical constructing of optimum regulators withthe input in their structures of such essences as intellectual agents as observers of complete order. Results of research. Management by the mining and processing complexes it is perspective to carry out on the basis of the quasi-optimal systems of management. Taking into account properties and sensitiveness of intellectual agents, expediently to include them at the analytical constructing of regulators in the structure of observers of complete order. This increases in accordance with securing functional of quality criterion of exactness of optimum stabilization of rational technology of process of growing shallow in the drum mills. Scientific novelty. A new structure is set of the quasi-optimal system of management by the technological dynamics of drum mills with the asymptotic observer of complete order. Of efficiency of recognition and operative management it is suggested to carry the rise out on the basis of functional possibilities of intellectual agents of targets, as which an observer comes forward of complete order in aggregate with the considered technological processes in the mining and processing complexes. Practical value. Results of researches allow to recommend a rational chart of quasi-optimal management by the drum mills in accordance with the set criterion. In the spectrum of the active power consumable by the drive electric motor technological constituents are selected, which are conditioned by the difficult vibrations of ore mass of filling of drum. Their maximal values are selected ekstremum by detector and are watched by the observer of complete order with the optimum stabilization. This allows to secure intensification of return of the prepared class.
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SHARP, W. B. A. SANDY, and W. A. BILLY JONES. "Evaluation of near-drum thinning data in recovery boiler generating bank tubes." July 2016 15, no. 7 (August 1, 2016): 491–500. http://dx.doi.org/10.32964/tj15.7.491.
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Near-drum thinning affects the fireside surface of recovery boiler generating bank tubes near the surface of the mud drum. Although sophisticated thickness scanning equipment has been developed to rapidly make tens of thousands of thickness measurements in the portion of a tube that is vulnerable to near-drum thinning, methods for using these data to evaluate fitness-for-service have not shown similar advances. Non-destructive testing companies typically use a technician’s subjective judgment to identify the “thinnest reliable" thickness measurement on each tube. Some mills decide whether tubes can continue in operation or should be plugged or replaced based on this single thickness measurement. However, finite element analysis of the remaining strength of individual tubes thinned in the near-drum area suggests that it is essentially impossible to identify the weakest tubes from simple empirical rules. In the absence of an industry standard for evaluating these data, different mills could reach different conclusions about the fitness-for-service of a tube from the same data set. This paper reviews the technology for scanning the thickness of generating bank tubes and discusses approaches that have been used to identify the tubes most weakened by near-drum thinning and to evaluate the fitness-for-service of individual tubes.
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Chyrkun, Dzmitry Ivanovich, Aliaksandr Eduardovich Leudanski, Vladimir Grigorievich Golubev, Didar Sarsenbekuly, and Serik Arginbaevich Kumisbekov. "ANALYSIS OF INDUSTRIAL DRUM MILLS’ OPERATION AND WAYS OF THEIR IMPROVEMENT." SERIES CHEMISTRY AND TECHNOLOGY 6, no. 432 (December 15, 2018): 102–8. http://dx.doi.org/10.32014/2018.2518-1491.32.
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Vynohradov, Borys, Veronika Karpenko, Olena Lahoshna, Kostiantyn Bas, and Iryna Slovska. "The ways to enhance durability and bearing capacity of the open gear drum mills." Mining of Mineral Deposits 15, no. 3 (September 2021): 87–94. http://dx.doi.org/10.33271/mining15.03.087.
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Purpose is substantiating ways to enhance durability and bearing capacity of open gears of ore-pulverizing drum mills as well as efficiency of engineering solutions concerning the increase in their unit power at the expense of drive improvement. Methods. Results of continual experiments and theoretical studies have been generalized as for the abrasion of working surfaces of open gear teeth of drum mills and factors influencing load distribution in terms of a tooth rim width. Findings. Comparative analysis between domestic mills and the best world-class products has been carried out. Ways of solving problems to design large-capacity mills with a gearbox drive have been demonstrated. Influence of hardness of working teeth surfaces on their durability has been evaluated quantitatively. The factors, governing load distribution in terms of tooth rim width, have been analyzed. Use of self-adjusting gear drives for open gears has been evaluated. Originality. Functional relation between stress-strain properties of working surface of teeth; the number of running-in modes, determined by operational conditions; and durability of open gear has been identified. The factors, influencing load distribution in terms of tooth rim width, have been considered. Practical implications. It has been shown that use of such open gears, where hardness of working surface of gear teeth is (500-600) H1B1 and that of a tooth rim one is (260-300) H2B2, makes it possible to provide almost wear-free operation. Moreover, it is the required condition for the performance of a tooth rim with two drive gears.
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Pershin, V. F., G. B. Zhumagaliyeva, A. G. Tkachev, A. A. Pasko, and A. M. Vorobyev. "Production of graphene concentrates based on synthetic oils in rod drum mills." IOP Conference Series: Materials Science and Engineering 693 (November 28, 2019): 012035. http://dx.doi.org/10.1088/1757-899x/693/1/012035.
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Mikulionok, Іgor, Аnton Karvatskii, Serhii Leleka, and Olena Ivanenko. "Roll crushers and mills (Design review)." Proceedings of the NTUU “Igor Sikorsky KPI”. Series: Chemical engineering, ecology and resource saving, no. 1 (March 29, 2022): 30–43. http://dx.doi.org/10.20535/2617-9741.1.2022.254157.
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The classification of roll crushers and mills for the disintegration of lumpy and loose materials processed at the enterprises of chemical, mining, construction, food and electrode industries, as well as in metallurgy, has been developed. A critical review of the most typical designs of roll crushers and mills proposed by scientists, designers and inventors of the world’s leading countries has been performed. The designs are analyzed according to the number of rolls, type of roll surface, shape of rolls, relative speed of working surface of rolls, possibility of roll surface temperature control, availability of additional working elements, as well as roll surface material.
Analysis of the designs of roll crushers and mills for the disintegration of lumpy and granular materials shows that they exist in numerous standard sizes, but conventional two-roll crushers with smooth, fluted and toothed rolls remain the most demanded by industry. In this case, the most promising area for improvement of roll crushers and mills is to develop designs of crushing elements for the working surface of rolls and materials for their manufacture.
In the future, it is planned to analyze the designs of other types of crushing equipment widespread in industry, such as jaw crushers and drum mills, as well as ways to improve their efficiency.
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Ostanovsky, Alexander. "IMPROVING THE EFFICIENCY OF FUNCTIONING OF DYNAMIC AUTOGENOUS MILLS DUE TO CYCLICAL DRUM BRAKE." University News. North-Caucasian Region. Technical Sciences Series, no. 2 (June 2016): 84–89. http://dx.doi.org/10.17213/0321-2653-2016-2-84-89.
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Koval', G. I., and Т. G. Kаrimоvа. "Calculation of roll calibration of rolling-forging mills using the rolling pattern “smooth drum – circle”." Bulletin of the South Ural State University Series ‘Metallurgy’ 16, no. 1 (2016): 72–77. http://dx.doi.org/10.14529/met160110.
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Федоренко, Mikhail Fedorenko, Бестужева, Olga Bestuzheva, Бондаренко, and Yuliya Bondarenko. "DETERMINATION OF RATIONAL PARAMETERS OF ROTARY SURFACE TREATMENT ROTATION WHEN RESTORING LARGE PARTS." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 1, no. 12 (November 11, 2016): 121–25. http://dx.doi.org/10.12737/22647.
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In various industries for production of cement, lime, gypsum, ceramic products for grinding solid materials using ball tube mills. In the process of operation under load of the mill, the wear of the main bearings of the drum tube mills – axles, with the result that on the surface appear different defects. The quality and performance of cement plants are directly dependent on the accuracy of its reconstruction, repair and content validity, determining largely technical and economic effect from the use of modern technical devices. Mill work in the area of large dynamic loads, leading to loss of efficiency and as a result long downtime to repair. With a view to their reduction, currently, to restore industrial equipment used in portable machines. Optimization of processing of surfaces of rotation when restoring large parts will allow you to obtain a rational combination of the varied parameters.
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Antimonov, Aleksey, and Nadezhda Pushkareva. "Fuel Pipes Coil Drawing Line Production for Diesel Engines." Materials Science Forum 946 (February 2019): 739–43. http://dx.doi.org/10.4028/www.scientific.net/msf.946.739.
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The technology and equipment for diesel engines steel fuel pipes cold rolling and coil drawing production on a self-aligning mandrel are considered. We presented current production line scheme for the pipes production, which includes pipe-rolling drum mills, radial forging machines, thermal furnaces with a protective atmosphere, finishing lines for unwinding coils and straightening pipes, a system of conveyors and stores for transferring coils from one unit to another. A list of articles and patents containing basic information on this topic is attached.
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Sharapov, Rashid. "Determination of the granulometric composition parameters of the grinding product in a ball mill." MATEC Web of Conferences 251 (2018): 03010. http://dx.doi.org/10.1051/matecconf/201825103010.
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The article deals with the issue of the formation of the grain composition of the comminuted material inside the drum of a ball mill. The approach to the calculation of the grain composition at its transition from a larger fraction from a smaller fraction is presented. The proposed approach was tested on an industrial cement ball mill and confirmed on an experimental installation. This approach allows you to determine the parameters of the kinetics of grinding, depending on the design parameters used ball mills.
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Ward, Julie, Helen Frances Mills, and Alan Anderson. "Drama in the Dale: Transformation Through Community Drama." Harvard Educational Review 83, no. 1 (March 26, 2013): 54–61. http://dx.doi.org/10.17763/haer.83.1.k746345q366v0023.
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During the winter of 2011-2012, Weardale, England, was the setting for an ambitious informal adult education project. In this rural area in the northeast part of the country, the local arts collective, Jack Drum Arts, established a community play project entitled The Bonny Moorhen. This dramatic undertaking aimed to retell the story of the infamous Battle of Stanhope, a local lead miners’ uprising. The project took place in a converted barn and involved a group of sixty learners of all ages and from all walks of life. The troupe formed the choir, band, backstage crew, and company of actors who, with the support of professional artists, built a temporary theater space. Each member of this collective made a personal journey. Here Helen Mills and Alan Anderson, in association with Julie Ward, cofounder and project producer at Jack Drum Arts, offer their personal testimonies from the project.
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Kamarova, Saule, Saule Abildinova, Angel Terziev, and Galym Baydusenov. "Improving the efficiency of the coal grinding process in ball drum mills at thermal power plants." Eastern-European Journal of Enterprise Technologies 1, no. 1 (115) (February 24, 2022): 93–105. http://dx.doi.org/10.15587/1729-4061.2022.253034.
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Ensuring the reliable operation of the dust fuel preparation system at thermal power plants (TPP) is a topical issue since it determines the energy strategy of any country that fires coals for thermal energy production. This unit is one of the most energy-intensive units in TPP. Those systems are outdated, poorly automated and high energy-intensive. Furthermore, they must ensure efficient and safe operation of the facility while being environmentally friendly. The current work focuses on the process of grinding coals in ball drum mills for further pulverized combustion. An experimental study was performed in order to determine the main factors (rotational speed of the drum mill, the degree of loading with the grinding balls, and the velocity of the supplied air) that affect the efficiency of the fuel preparation system. The obtained experimental data and performed mathematical modeling resulted in regression equations describing the energy performance of the mill. Three regression equations for mill productivity, power consumed, and specific surface area of the final product were obtained and validated. The study reveals that the lowest specific energy consumption is achieved when the relative rotational speed of the mill is between 0.81 and 0.87; the weighted average diameter of the balls ranges from 33.5 up to 34.5 mm; the load factor of the grinding media ranges from 0.325 up to 0.335, the supplied air velocity is between 0.2 and 0.3 m/s. The proposed methodology allows adjustment of the operating parameters of the grinding process to achieve the lowest energy consumption. The power consumption for the preparation can be reduced up to 5 % for the selected operation mode of the grinding facility.
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Minin, Ivan. "Research on the relative productivity of a drum mill type SAG 8.5×5.3." E3S Web of Conferences 168 (2020): 00012. http://dx.doi.org/10.1051/e3sconf/202016800012.
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The determination of the optimal operational mode of drum mills can be assessed by different criteria. The most important of them can be formulated as follows: “To be specified and established the values of the mill operational parameters regarding to which it is possible to be provided the user’s expected performance at the required quality of the final product and the same to be achieved at minimal energy consumption”. For the fulfillment of this condition, there has to be determined the laws of productivity variation, the final product quality and the energy consumption in function of the adequately chosen representative control parameters of the mill. There are obtained mathematical models, describing the most important technological parameters of the machine and are made conclusions about the factors influencing on them.
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Meshcheriakov, L., O. Galushko, O. Syrotkina, and O. Demidov. "Recognition of technological states of drum mills on the basis of neuron networks of adaptive resonance." Collection of Research Papers of the National Mining University 57 (March 30, 2019): 129–37. http://dx.doi.org/10.33271/crpnmu/57.129.
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Meran, Cemal, and Mehmet Yuksel. "Usability of Boron as an Alloying Element in Gray Cast Iron Rollers and its Effect to Abrasive Wear Behaviour." Advanced Materials Research 445 (January 2012): 331–36. http://dx.doi.org/10.4028/www.scientific.net/amr.445.331.
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In this study, usability of boron as an alloy element in gray cast iron and its effect to abrasive wear behaviour were investigated. Pin-on-drum wear tests at the room temperature carried out for seven low nickels alloyed gray cast irons with different boron addition. The mass losses, hardness values and microstructures for gray cast iron specimens with different boron alloyed were investigated for determining wear behaviour. The pin for the wear tests was manufactured from X210Cr12 cold work tool steel with material number of 1.2080. Abrasive pin-on-drum wear tests were carried out at a 165 N constant load and two different sliding speeds that are closely related to the appropriate operating conditions in rolling mills. The experimental studies have shown that wear rate decrease with increasing boron amount in chemical composition of the alloy and the wear rate at high sliding speed has decreased more rapidly than the rate at the low sliding speed with increasing boron amount.
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Golik, V. I., and A. V. Titova. "Combined activation technologies mineral raw materials." Mining Industry Journal (Gornay Promishlennost), no. 5/2021 (November 12, 2021): 100–105. http://dx.doi.org/10.30686/1609-9192-2021-5-100-105.
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Relevance. The efficiency of using the products of subsoil exploitation is a factor in strengthening the mineral resource base of the mining industry. The success of improving ore preparation technologies is associated with the activation of mineral raw materials in mills, including impact mills – disintegrators. A fundamentally new approach to ore processing technology includes a combination of grinding methods in mills and other activators. The issues of increasing the activity of substances on the basis of combination form an urgent scientific and industrial problem. The aim of the study of the phenomenon of combined activation is to search for the possibility of increasing the level of activation, to ensure the stability of the acquired activity and to establish patterns of relationships between the activation processes and the technological processes of using mineral raw materials. Objects: products of the development of deposits of solid mineral raw materials in various mining sectors of the national economy. Methods: Laboratory, semi-industrial and industrial experiment using improved equipment for the activation of mineral raw materials. Results. The concepts of “mechanical activation” in mills and “activation with large mechanical energy” in a disintegrator are detailed. An assessment is given to the directions of improving the mills. The results of mechanochemical activation of powders oxides in a planetary centrifugal mill “Aktivator-2s” are given. The practice of activating mineral raw materials with a combination of activators of various types is described. It has been established that the efficiency of combining mills depends on the initial size of the crushed material and equipment options are recommended depending on this. It is shown that the combination of drum and vibration mills reduced the energy consumption of the product. The results of the combination and the vibrating mill in the technological chain of the concrete complex are presented. The algorithm for the combined activation of mineral raw materials is illustrated by the example of the technology applied at the mine, which includes grinding, mixing binders, inert aggregates and grout, as well as transporting the concrete mixture to the place of use. As a quantitative indicator of activation, an equivalent of activity or a proportional ratio of the combined components is proposed. The efficiency of using solid mineral raw materials increases when it is prepared in activators.
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Kalhankov, Ye V. "Some issues of resource and energy saving in crushing of mineral raw materials in drum ball mills." Geo-Technical mechanics, no. 151 (2020): 138–49. http://dx.doi.org/10.15407/geotm2020.151.138.
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Isokangas, Ari, Kari Ala-Kaila, Markku Ohenoja, Aki Sorsa, and Kauko Leiviskä. "Effect of log loading on the performance of wood room." Nordic Pulp & Paper Research Journal 29, no. 2 (May 1, 2014): 201–10. http://dx.doi.org/10.3183/npprj-2014-29-02-p201-210.
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Abstract The purpose of this paper is to analyse the log loading process of wood room, which is typically the first processing unit in pulp and paper mills. The aim is to improve the log loading process to obtain production with a constant log flow of well de-iced logs to the debarking drum. This way it is possible to reduce costs and enhance product quality. The research was carried out utilising a log loading simulator. The parameters of the simulation model were selected on the basis of process observations on a mill. The results indicate that it is essential to adjust the process and equipment parameters, raw material properties and truck loader operation together in order to reach the target capacity with minimum costs. Especially the speed of the infeed conveyor affects all performance criteria and should be selected carefully. In addition, wood yard logistics and raw material properties have a remarkable effect on the wood room performance. The results can be utilised in mills to allow the upper level control perform in a planned way so that small wood loss and good product quality can be obtained.
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Nazarov, V. I., V. M. Retivov, A. M. Gonopolsky, D. A. Makarenkov, A. P. Popov, and G. R. Aflyatunova. "Study of the Technology of Using Complex Lithium-Сobalt Current Sources Using Combined Processes of Mechanical Processing, Leaching and Extraction." Ecology and Industry of Russia 26, no. 5 (May 3, 2022): 10–16. http://dx.doi.org/10.18412/1816-0395-2022-5-10-16.
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It is shown that the disposal of spent complex chemical power sources (CPS) leads to severe environmental pollution. An environmentally safe technology for their disposal has been developed, including the stages of mechanical processing, leaching and extraction. The article discusses the combined processes of processing spent CPS with the use of mechanochemical destruction. The work of opening the CPS on a shredder in an argon atmosphere, knife and ball mills is analyzed. The grinding of model media with different morphology in a drum mill and a toroidal vibrating mill (TVM) was studied, and the operating parameters of the drum mill in a waterfall mode were determined. A narrowing of the granulometric composition from a particle diameter of 2–3 mm to a diameter of 10–40 microns was revealed. It is shown that when CPS particles are ground in a ball mill at a ratio of balls and ground phase of 5:1, the content of cobalt in the powder increases to 19.0 wt %. The time for the complete cycle of CPS processing, including the stages of opening in an argon atmosphere, grinding, grinding, leaching and extraction, was established to be 7 hours.
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Makarenkov, D. A., and V. I. Nazarov. "Characteristics of mechano-activation in vibratory pulverizers and drum mills in the preparatory and granulation stages of disperse media." Chemical and Petroleum Engineering 47, no. 1-2 (May 2011): 121–32. http://dx.doi.org/10.1007/s10556-011-9435-9.
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Novitskyi, I., V. Sliesariev, and A. Maliienko. "The basic principles of organizing prospecting procedures for managing the process of autogenous grinding of ores in drum mills." Collection of Research Papers of the National Mining University 66 (2021): 245–53. http://dx.doi.org/10.33271/crpnmu/66.245.
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Saunamäki, R. "Sludge Handling and Disposal at Finnish Activated Sludge Plants." Water Science and Technology 20, no. 1 (January 1, 1988): 171–82. http://dx.doi.org/10.2166/wst.1988.0020.
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Between 1984 and 1986 a total of 13 activated sludge treatment plants were built in Finland to handle waste waters from the pulp and paper mills. With just a few exceptions these plants have come up to expectations, achieving BOD7 reductions of 80-95 %. These plants produce around 94,000 tonnes (dry weight) of sludge a year, of which some 27,000 tonnes is biosludge. On a mill basis, biosludge accounts for 10-50 % of total sludge. Generally speaking, the higher the loading at the plant, the more biosludge is produced. The yields of biosludge were 0.3-1.2 kgTS/(kgBOD removed) for a sludge load of 0.1-1.2 kgBOD7/(kgMLVSS*d). The biosludge is separated by sedimentation in clarifiers and thickened in round sedimentation basins to a consistency of 3-5 %. At one mill anaerobic sludge from an oversized thickener is returned to the aeration basin. The aim of this is to minimize the need for nutrient addition. Belt filter presses are normally used for sludge dewatering, the solids contents achieved being about 25-37 %. The difficulty of handling biosludge and the low solids contents achieved were considered by many mills to be the main problems of sludge handling. At one mill a drum press is used to press a pretreated mixture of sludge and bark to around 42 % consistency for burning. Six mills burn all or part of their sludge in a bark-fired boiler. On a dry weight basis the sludge burned normally accounts for 5-10 % of total fuel consumption. Burning sludge has been associated with a reduction in steam generation and an increase in running problems. The other method of disposing of sludge is landfilling. Sludge is not used as a fertilizer or soil improvement agent in Finland.
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Monastyrskyi, Vitalii, Serhii Monastyrskyi, and Borys Mostovyi. "Effect of water medium upon the process of ore disintegration in wet self-grinding mills." E3S Web of Conferences 109 (2019): 00058. http://dx.doi.org/10.1051/e3sconf/201910900058.
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This article presents the results of theoretical and experimental studies on the processes of destruction ore in wet self-grinding mills under the influence of the aquatic environment on it. The equivalent circuit for determining the stress-strain state of a large piece (ball) exposed to the load at an angle of repose of the material in motion are justified. A uniformly distributed pressure acts on the body of arbitrary shape, depending on the hydrostatic pressure of the pulp inside the drum and the force of hydrodynamic resistance). It is assumed that a large piece has the shape of a sphere with a uniform structure, but in some of its parts there are cavities filled with an incompressible fluid. Under the action of these forces inside the cavity wedging effects of water occur, the effect of which on the strength ores depends on the expansion force and the angle of the micro crack. The experimental researches are done under laboratory and industrial conditions. It was established that the disintegration of kimberlitic ore in MMC is significantly influenced by the characteristics of the aquatic environment pH and Eh, the values of which vary from 3.2 to 7.0 and from -500 to +1020 mV.
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Vernigorov, Yuriy, Valeriy Lebedev, Natalya Frolova, and Kirill Leletko. "Network high-performance grinding devices for ferromagnetic materials." E3S Web of Conferences 135 (2019): 02019. http://dx.doi.org/10.1051/e3sconf/201913502019.
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The design features of the grinding devices that implement the impact destruction of the ferromagnetic materials particles in a magneto vibrating layer formed in a non-uniform magnetic field are considered. It is shown that when a magnetizable powder is affected by an alternating magnetic field with certain parameters, a magneto vibrating layer is formed, under the conditions of which, a random perturbing factor occurs. It is caused by the dipole particles clusters interactions and provides highefficient finish powder grinding. Methods for producing metal powders, which are distinguished according to the operating principle and to the requirements for the technological properties of the powders obtained, are analyzed. For coarse grinding, jaw, roller and cone crushers and mullers are used; at this, particles of 1-10 mm in size, which are the source material for fine grinding, are obtained. The finish grinding of the material obtained is carried out on the ball rotating, vibrating or planar centrifugal, vortex and hammer mills. The main drawback of these techniques of metal powder grinding is sticking of grinding body residue on the powder particles, which reduces the quality and operational properties of the powder. A relation to calculate the dependence of the fineness number of ferromagnetic materials on the induction gradient of an external variable magnetic field is proposed. The design features of an electromagnetic mill based on a screw drum that, due to the spatial orientation of its walls, ensures an effective movement of powder flows inside it, such as mixing, rotation, oncoming movement, translational motion and simultaneous advancement through the drum are presented. The concept and technological options of grinding powders in an electromagnetic mobile hammer mill are revealed, which enables to obtain a powder of a given particle size distribution with high uniformity. It is established that mills in which a magneto vibrating layer is implemented are more effective than mechanical ones: grinding of ferromagnetic powders in a magneto vibrating layer increases drastically the performance of the grinding process. Changing the parameters of the electromagnetic field, you can set an average particle size and the degree of homogeneity of the powder.
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Sevostyanov, Vladimir S., Nikolai T. Shain, Svetlana V. Sverguzova, Maxim V. Sevostyanov, Dmitry N. Perelygin, and Alexey V. Uralskij. "Resource-energy-saving technologies and equipment for complex processing of man-made materials." Image Journal of Advanced Materials and Technologies 6, no. 4 (2021): 279–90. http://dx.doi.org/10.17277/jamt.2021.04.pp.279-290.
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Using the fundamental kinetic laws of materials grinding processes, a resource-energy-saving technology for complex processing and mechanoactivation of mineral components has been developed. For the technology, patent-protected energy-efficient grinding units for selective grinding of materials have been developed: press-roll grinders (PRG) for volume-shear deformation (VSD) of materials and obtaining their microdefect structure; drum ball mills (DBMs) with internal energy-exchanging devices (IEDs), which implement impact-crushing-abrading action with less 10–20 % grinding load. A technological complex was developed for mechanoactivation of fine-grained materials and obtain nanostructured composite mixtures from them: “PRG–VSD”– vibration-centrifugal unit (VCU) of selective grinding at each stage – vortex-acoustic dispersants (VADs) for obtaining ultrafine particles < 5 μm with mechanical-aerodynamic and acoustic grinding. Resource-energy-saving technology has been tested for complex thermomechanical processing of quartzite-iron-containing was teat the Lebedinsky mining and processing plant for production of pigments-fillers for the purpose of volumetric dyeing of products.
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Rakhmanov, S. R. "Some peculiarities of the process of the pipe purse firmware on the firmware." Metallurgicheskaya i gornorudnaya promyshlennost, no. 1 (2019): 31–39. http://dx.doi.org/10.33101/s001-1700087840.
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Purpose. Conducting research aimed at choosing the rational modes of flashing the tubular billet by stabilizing the dynamic characteristics of the drive power line of heavy-duty piercing mills TPA. Methodology. The dynamics of the power line of the piercing mill of the pipe-rolling unit (TPA) are considered, taking into account the peculiarities of the behavior of the spindle hinges and the mechanism for setting the work rolls. Findings. The differential equation of motion of the line of the main drive of the piercing mill is composed and its numerical solution is given. An adapted three-mass dynamic model of the system is considered and a solution is obtained using the software Solid Works IT Simulation X. The basic conditions for the occurrence of unstable dynamic phenomena in the fieldline and the installation mechanism of the piercing mill rolls are formulated. It is shown that the unstable dynamics of the system are one of the main reasons for the discrepancy between the results of well-known theoretical, experimental studies and pipe thickness measurement at TPA 350 piercing mills. Originality. The main causes of the emergence of parametric oscillations in the drive of the working stand of the piercing mill, the installation mechanism of the work rolls in connection with the mechanism of formation of the thin-wall thickness of pipes are established. The areas of stability of the system’s functioning are determined depending on the operating modes and the angle of feed of the work rolls, taking into account the spatial position of the elements of the spindle device. The necessary and sufficient stability conditions for the joint stable functioning of the power line elements of the piercing mill are formed. Practical value. To stabilize the processes for flashing the tubular billet, a scheme has been proposed for upgrading the spindles of the main drive and the mechanism for installing the work rolls of the piercing mill No. 1 of TPA 350. The results are applicable to similar helical rolling mills. Keywords: firmware, billet, mill, pipe, uneven stroke, varying thickness, dynamics, drive, roll, oscillations, spindle, Cardan, hinge, moment of inertia, rigidity, drum, installation mechanism, stability.
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K. V. N. N. Jayalath and U. K. Jayasinghe-Mudalige. "Quest for Better Technology: Case of Brown Coir Fibre Industry in Sri Lanka." CORD 25, no. 2 (October 1, 2009): 10. http://dx.doi.org/10.37833/cord.v25i2.140.
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The purpose of this study was to assess the impact of a number of attributes (a = 23) upon 5 major factors (Labor, Land and Capital, Machine, Technical and Market) that influence a selection of a particular technology to manufacture brown coir fibre in Sri Lanka (i.e. Sri Lankan Drum Pairs, Defibering Machine, D1 Machine). A cross section of owners of fibre mills (n = 30) located in the Kurunegaka, Puttlam and Gampaha districts were selected and a personal interview with each mill owner was carried out with the help of a structured questionnaire from May to June 2008 to collect data. The Semantic Differential Analysis techniques were employed to find the relative strength of the attributes of 5 factors considered in the analysis, where the responses were recorded on a seven-point bipolar scale. The “XLStat” software was used extensively to plot the relationships between the 23 attributes and 3 technologies.
The results suggest that all three technologies are negatively perceived by the coir fibre millers on land and capital, and machine subsets. Further millers had negative perception on attributes related to labor subset of Sri Lankan Drum Pair technology. However, they hold the view that high quality of the bristle fibre extracted by this machine is not comparable with that extracted using any other technologies. The millers’ perception on technical and market attributes of the three different technologies was better than on other attributes.
The results imply that policymakers should, more specifically, take into account the issues related to capital, machine and labor as they advise coir fibre manufactures about possible technology transfer, in order to avoid potential failures in these markets (i.e. plant-exit) and government policy (i.e. non-compliance).
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Didyk, R. P., and O. M. Cherkashchenko. "Revivification of the Hard Alloys by Shock Waves." Advanced Engineering Forum 14 (October 2015): 19–22. http://dx.doi.org/10.4028/www.scientific.net/aef.14.19.
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The purpose. To work out an efficient technology and develop production of supersolid metal-ceramic powders and tools of high quality from processed raw materials.Methods. To stimulate the processes of defect formation and destruction of tungsten containing alloys under conditions of the effect of high pressure gradients and loading rate revivified by shock waves of different intensity.Results. This is the first time explosion energy has been applied to grind hard alloys in cylindrical capsules compared to the traditional methods of recycling. The material obtained in the capsules of impact compression was exposed to finely dispersed structure refinement in drum-type grinding mills with duration 20 times as short as that for the current grinding technology which allowed decreasing energy consumption for grinding process by 7.75 megawatt for one aggregate onlyScientific novelty. Shock waves generated by detonation of condensed explosives have been originally used as tools to stimulate the processes of defect formation of cemented carbide alloys at different scale level. Conditions of preserving the shocked product in axial symmetry facilities has been developed and provided.Practical implications. The use of shock waves in the technology of hard alloy revivification is the only possible method of processing large-size solids with significant reduction of energy consumption and quality-assured production.
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Naumenko, Yuriy, Kateryna Deineka, and Tamara Myronenko. "Establishing the conditions for the formation of a near-wall layer of solid granular fill of a rotating drum." Eastern-European Journal of Enterprise Technologies 5, no. 1(113) (October 31, 2021): 51–61. http://dx.doi.org/10.15587/1729-4061.2021.240194.
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This paper reports the assessment of the influence of dynamic motion parameters on the formation and disappearance at the cylindrical surface of the chamber of the rotating drum of the near-wall layer of non-loose granular fill. Based on the results of experimental visualization of the flow, the effect of solidity on the behavior of granular fill was revealed. The hydrodynamic effect of fill quasi-liquefaction under the action of solidity has been established, which involves the occurrence of a connecting interaction between adjacent layers and the surface of the chamber. Conversion of shear circulation flow to homogeneous dense clustered stream with slipping and rolling without relative movement of particles was detected. The hydrodynamic characteristics of circulation flow transition to the near-wall layer mode during rotation acceleration have been defined. Such a transition is implemented by smoothly increasing the thickness of the layer when the rest of the fill is circulated at the bottom of the chamber. The effect of the rheological hysteresis of the movement of the rotating chamber fill, caused by quasi-liquefaction of non-loose granular environment, has been established. The effect implies exceeding the speed limit ωfl in the formation of a near-wall layer, at rotation acceleration, above the boundary ωdl of the layer disappearance when the rotation slows down. The manifestation of hysteresis mainly increases with an increase in Reynolds number. The intensity of increased hysteresis manifestation increases with a decrease in the degree of filling the chamber. The value of the Froud number for the ωfl and ωdl boundaries increases with the increase in Re. It has been established that at the relative particle size of the dispersed fill ψdc≈(0.065–1.04)·10‑3 and Re=30–500, Fr=1–2.9, for the ωfl boundary, and Fr=0.5–1.4, for the ωdl boundary. The Fr value for the ωfl limit was found to exceed this value for the ωdl boundary by 1.6–2.1 times. The established effects make it possible to substantiate the rational parameters for the grinding process in drum-roll mills
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Umanskii, A. A., A. V. Golovatenko, T. N. Oskolkova, A. S. Simachev, and A. G. Shchukin. "INFLUENCE OF MACRO- AND MICROSTRUCTURE OF STEEL GRINDING BALLS ON THEIR IMPACT RESISTANCE." Izvestiya. Ferrous Metallurgy 62, no. 4 (June 20, 2019): 283–89. http://dx.doi.org/10.17073/0368-0797-2019-4-283-289.
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Based on the analysis of the literature and production data, it is shown that the wear resistance of steel grinding balls, which are the main grinding medium for crushing various types of raw materials in the drum type mills, is determined not only by hardness of the surface layer, but also by the quality of their macro- and microstructure. At the same time, there is a complex nature of dependences of the balls impact resistance on the above mentioned parameters with their simultaneous impact, which determines the relevance of research in this direction. Series of experimental studies was carried out in order to obtain scientifically based dependencies of impact resistance of grinding balls on the quality of their macro- and microstructure. The grinding balls with a diameter of40 mm,50 mmand60 mmproduced by OJSC “EVRAZ ZSMK” (Novokuznetsk) and by JSC “Industrial Solutions” (Nizhny Tagil) were used. The research was carried out by metallographic, durometric and fractographic methods of analysis; tests of grinding balls on the impact resistance were performed on the impact drop machine. According to the results of metallographic studies it was determined that the volume-hardened balls are characterized by a three zone structure. The surface hardened layer with a depth from 1.9 to7.4 mmis martensite. The transition zone with thickness from 1.0 to1.7 mmhas a structure martensite + troostite. The central zone occupies the entire remaining volume of the ball and has several varieties of microstructure: ferrite + perlite, martensite + troostite + ferrite, martensite + troostite. On the basis of generalization of the obtained experimental data, it was established that at surface hardness of balls within 42 – 52 HRC the quality of macrostructure (presence of flakes) is the parameter determining impact resistance. For balls with high surface hardness (57 – 61 HRC) the most significant impact on impact resistance is provided by non-uniform microstructure of metal, which causes a significant difference in hardness across the balls crosssection.
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KLYKOV, Yuri, Marina KHUDOYAN, and Georgy KIBIZOV. "DETERMINATION OF THE MECHANISM FOR OPENING QUARTZ PARTICLES WHEN GRINDING QUARTZ-CONTAINING PRODUCTS IN A CENTRIFUGAL MILL." Sustainable Development of Mountain Territories 12, no. 3 (September 30, 2020): 454–60. http://dx.doi.org/10.21177/1998-4502-2020-12-3-454-460.
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Introduction. Currently used grinding machines, among which drum mills are the most widely used, have a low efficiency, are bulky, are characterized by low specific productivity, significant consumption of steel for grinding bodies and lining, high noise level, and high energy consumption of the grinding process. The most promising devices of a new type that can effectively perform grinding operations at high technological rates are centrifugal mills. The centrifugal mill developed at SKGMI operates on the principle of self-grinding of pieces and particles of crushed mineral raw materials, when they collide and RUB in a mobile toroidal flow formed when the material moves between a rotating Cup-shaped rotor, a fixed body and the overlying layers of the crushed material. Grinding occurs due to the appearance of a gradient of particle velocities over the working body, due to their impact and, to a greater extent, abrasion. The tests of these mills for grinding various materials have shown high efficiency in operation, but until now, the issues of determining the physical and mechanical properties of the crushed material based on the establishment of the particle opening mechanism remain unresolved. The purpose of the tests. Determination of the physical and mechanical properties of the crushed material in a centrifugal mill based on the establishment of the particle opening mechanism. Test procedure. To solve this problem, a vertical centrifugal mill MC-600 with a rotor diameter of 600 mm was used. Tests of the centrifugal mill were carried out according to the following method. The speed of rotation of the rotor was 4.8 and 8.4 s-1, the height of the material column above the rotor was at the level of 250 and 350 mm; 6 radial ribs were installed in the rotor cavity of the mill. The time of each test was 4 hours. The tests were repeated 3–5 times for each mode of operation of the mill. Quartz was used as a reference material for determining the relative pulverizability coefficient. The research was carried out in the production conditions of the Izhevsk machinebuilding plant during the regeneration of spent molding quartz mixtures. Pieces of a liquid-glass mixture based on quartz sand with strength of 1.3 MPa and 4.25 MPa were used as the crushed material. The crushed material was dispersed according to the standard method for each hour of operation of the mill. Samples were taken in the size class -0.200 + 0.074 mm for their fractional analysis by size. Test result. 1. It was Found that the maximum productivity of a centrifugal mill when grinding pieces of material with a strength of 1.3 MPa was achieved with a loading weight of 90–100 kg, and with a strength of 4.25 MPa – 100–110 kg, which indicates the need to create an increased normal pressure of the layers of crushed material located above the mill rotor. It was found that the maximum productivity of a centrifugal mill when grinding pieces of material with a strength of 1.3 MPa and a rotor rotation frequency of 8.4 s-1 was 13.16 t/h, and when grinding pieces of material with a strength of 4.25 MPa – 10.0 t/h. 2. The Dependence of power consumption on the weight of the mill load and the rotor speed increases when the load weight is more than 100 kg. 3. The Highest fraction content of class -0.4 +0.16 mm is 72.14 %, and the content of class -0.074 mm is 3.9 %, i.e. there is no re-grinding of the source material. 4. The specific productivity of the centrifugal mill for the newly formed calculated size classes -0.074 mm and -0.200 mm was 1.28 t/h and 13.0 t/h, respectively. 5. Microscopic study of anshlifov showed that quartz grains in the crushed material mostly have a rounded shape, on average 90–95 % of the grains. In the initial material, about 90% of quartz joints with a binder, and in the crushed material, the number of joints does not exceed 3–5%. Thus, the degree of expansion of quartz reaches to 0.87. Conclusions. The paper presents the results of studies of a centrifugal mill in the conditions of the Izhevsk machinebuilding plant when grinding quartz-containing products. The physical and mechanical properties of the crushed material that significantly affect the efficiency of grinding are determined. The mechanism of the disclosure particles of quartz, which is primarily the mineral content of many ores and defined particle size obtained by grinding. At the same time, it was found that a large yield of thin classes significantly reduces the efficiency of further technology.
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Anisimov, Alexander V., and Felix Ya Rudik. "The Experimental Determination of Optimum Parameters of the Equipment for Processing Grain in Preparation for Grinding." Engineering Technologies and Systems 29, no. 4 (December 31, 2019): 594–613. http://dx.doi.org/10.15507/2658-4123.029.201904.594-613.
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Introduction. Modern technology of grain processing pays special attention to the qualitative and efficient preparation of grain for milling. At small enterprises with a reduced technological process, this is almost the only way to improve product yield and quality. Without proper multi-stage preparation of grain for milling at small enterprises, it is impossible to achieve the required quality and quantity of products produced by industrial mills. Grain peeling is one of the most effective ways to clean the surface from dirt and remove outer shells. The removal of outer shells allows increasing the yield of high-grade flour at reduced milling diagrams. The efficiency of the peeling process is significantly infuencet by the design and operating parameters of the peeling machine. The purpose of this work is the experimental determination of optimal conditions for grain processing in the peeling and drying machine (the optimal combination of factors). Materials and Methods. To determine optimal conditions for grain processing in the peeling and drying machine, the method of extreme planning of the experiment was applied. The method of random balance was used to select the most significant factors based on their influence on the optimization parameter. The method of steep ascent on the response surface (the Box – Wilson method) was used to find the optimum area (the planning matrix was realized and statistical analysis of results and steep ascent on the response surface was carried out). Verification of the results was carried out on the software Statistica 10.0. Results. On the basis of experiments, a mathematical model of the technological process of wheat processing in the peeling and drying machine there were obtained, which linked the structural and mode parameters of the machine with the humidity of the treated grain. The results of the experiment confirmed the operability of the developed machine when working with high-humidity grain; they are fundamental for the machine’s further modernization. Discussion and Conclusion The analysis of the controlled factor dispersion diagram allowed us to select the most significant of them based on influence on the selected optimization parameter, the white flour color obtained from the treated grain. As a result of the evaluation of experimental data of the conducted studies, the design and mode parameters of the developed machine were determined, corresponding to the areas of the optimal optimization parameter: shaft rotation speed is 1400 rpm, angle of inclination of stamping on the sieve drum is 15 degrees, the initial moisture content of the processed grain is 15.50%, and the machine productivity does not exceed 700 kg/h.
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Schwendner, Julia Felicitas, Christoph Konnerth, Stefan Romeis, Jochen Schmidt, and Wolfgang Peukert. "Formation of drug-loaded nanoemulsions in stirred media mills." Advanced Powder Technology 30, no. 8 (August 2019): 1584–91. http://dx.doi.org/10.1016/j.apt.2019.05.005.
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Gugelmann, Hallam, Jeanmarie Perrone, and Lewis Nelson. "Windmills and Pill Mills: Can PDMPs Tilt the Prescription Drug Epidemic?" Journal of Medical Toxicology 8, no. 4 (December 2012): 378–86. http://dx.doi.org/10.1007/s13181-012-0273-8.
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MÜRSELOĞLU-, Rüstem. "KIRGIZ TİYATROSUNA BİR BAKIŞ. KIRGIZ MİLLİ AKADEMİK DRAM TİYATROSU." Turkish Studies-Social Sciences Volume 14 Issue 3, Volume 14 Issue 3 (2019): 849–63. http://dx.doi.org/10.29228/turkishstudies.22817.
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HARRIS, KERRI L., GERD BOBE, and LESLIE D. BOURQUIN. "Patulin Surveillance in Apple Cider and Juice Marketed in Michigan." Journal of Food Protection 72, no. 6 (June 1, 2009): 1255–61. http://dx.doi.org/10.4315/0362-028x-72.6.1255.
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Patulin is the most common mycotoxin found in apples and apple juices. The objective of this study was to determine the concentrations of patulin in (i) apple cider produced and marketed by Michigan apple cider mills during the fall seasons of 2002 to 2003 and 2003 to 2004 and (ii) apple juice and cider, including shelf-stable products, marketed in retail grocery stores in Michigan throughout 2005 and 2006. End product samples (n = 493) obtained from 104 Michigan apple cider mills were analyzed for patulin concentration by using solid-phase extraction followed by high-performance liquid chromatography. Patulin was detected (≥4 μg/liter) in 18.7% of all cider mill samples, with 11 samples (2.2%) having patulin concentrations of ≥50 μg/liter. A greater percentage of cider samples obtained from mills using thermal pasteurization contained detectable patulin (28.4%) than did those from mills using UV light radiation (13.5%) or no pathogen reduction treatment (17.0%). Among retail grocery store samples (n = 159), 23% of apple juice and cider samples contained detectable patulin, with 18 samples (11.3%) having patulin concentrations of ≥50 μg/liter. The U.S. Food and Drug Administration (FDA) action level for patulin is 50 μg/kg. Some apple juice samples obtained from retail grocery stores had exceptionally high patulin concentrations, ranging up to 2,700 μg/liter. Collectively, these results indicate that most apple cider and juice test samples from Michigan were below the FDA action level for patulin but that certain apple cider and juice processors have inadequate controls over patulin concentrations in final products. The industry, overall, should focus on improved quality of fruit used in juice production and improve culling procedures to reduce patulin concentrations.
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Li, Yaoyu, Jie Bao, and Runyu Yang. "Acoustic signals of rotating drums generated based on DEM simulations." EPJ Web of Conferences 249 (2021): 14019. http://dx.doi.org/10.1051/epjconf/202124914019.
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Acoustic emission (AE) or vibration signal has been applied in detecting operations of grinding mills in many industries. This paper proposes an approach to generate AE signals based on the particle-wall impacts. Through a combination of multi-mode vibrations and the calibration of the key parameters, the model was able to reproduce experimental data. The AE model was then implemented into a discrete element method (DEM) modelling of particle flow in a rotating mill. The AE signals of the mill under different filling levels and rotation speeds were generated and analysed, mainly focusing on the frequency and magnitude of each vibration mode. The link between the AE signals and the particle-wall impact energy was explored.
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Lidbury, Clare. "Drums Sound in Hackensack: Agnes de Mille and the Jooss Ballet." Dance Chronicle 42, no. 2 (May 4, 2019): 195–216. http://dx.doi.org/10.1080/01472526.2019.1622992.
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Kemp, Simon, and Randolph C. Grace. "Operant contingencies and “near-money”." Behavioral and Brain Sciences 29, no. 2 (April 2006): 188. http://dx.doi.org/10.1017/s0140525x06359043.
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We make two major comments. First, negative reinforcement contingencies may generate some apparent “drug-like” aspects of money motivation, and the operant account, properly construed, is both a tool and drug theory. Second, according to Lea & Webley (L&W), one might expect that “near-money,” such as frequent-flyer miles, should have a stronger drug and a weaker tool aspect than regular money. Available evidence agrees with this prediction.
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Latifi, Farzam, Sirous Chehrazi, and Hossein Ansari. "Identification of Dextran and Sludge–Producing Bacteria in Sugar Cane Juices Using Polymerase Chain Reaction." Biosciences, Biotechnology Research Asia 14, no. 4 (December 25, 2017): 1337–41. http://dx.doi.org/10.13005/bbra/2577.
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ABSTRACT: The microbial contamination due to cane sugar transition to the mills is one of the most important factors in increasing sugar lesions in the factory. This study was aimed to isolate dextran-producing bacteria and determine their genus and species. It is a descriptive cross-sectional study which was conducted in year 2014. For this purpose, 200 samples were collected from sugarcane syrups, and then cultured as pourplate and surface. The bacteria were counted and the DNA extracted from the purified bacteria according to the kit protocol. Then, determination of the genus and species of dextran-producing bacteria was performed by polymerase chain reaction (PCR) using specific primers. Data obtained from biochemical, microbial and PCR showed that around 80 strains of leuconostoc have been detected in samples. The results of this study indicate that leuconostoc mesenteroides is the main factor in the production of dextran in sugarcane and beet manufactories. The above mentioned contamination sources can be minimized by reducing the transfer time of burned sugarcane to the factory, as well as the regular physical and chemical washing of the mills.
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OLSZEWSKI, Artur, Jacek Igor ŁUBIŃSKI, Witold PAWLOS, and Bogdan KUŹBA. "OPERATING CONDITIONS OF SLIDE BEARINGS OF MILLS USED IN KGHM POLSKA MIEDŹ S.A." Tribologia 268, no. 4 (August 31, 2016): 177–89. http://dx.doi.org/10.5604/01.3001.0010.6993.
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The paper contains the results from a technical analysis of the conditions of the operation of hydrodynamic bearings supporting the drums of ore processing mills at KGHM Polska Miedź S.A. A theoretical analysis was performed on the grounds of onsite examination and measurements of principal dimensions of the bearings of interest. The computer simulation covered the characteristics of the oil film in the bearings as a function of bearing clearance, load, lubricant viscosity, and journal tilting in relation to two planes (horizontal and vertical). The results of the analysis indicate that the bearings currently operate close to maximum capacity and that there is a significant deflection of the bearing journals under the applied joint load of the drum’s own weight and the process load of grinders and slurry. The current extent of tilting can cause oil film breakage at the bearing’s edge. The result of calculations amended by bearings’ examination and measurements allowed the formulations of conclusions regarding the current state of the bearings and evaluated load conditions. Guidelines were established for later developments in the capacity and reliability of the bearings.
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Mesnier, Aline, Roman Peczalski, Guilhem Mollon, and Séverine Vessot-Crastes. "Mixing of Bi-Dispersed Milli-Beads in a Rotary Drum. Mechanical Segregation Analyzed by Lab-Scale Experiments and DEM Simulation." Processes 8, no. 9 (September 17, 2020): 1166. http://dx.doi.org/10.3390/pr8091166.
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Mechanical flow and segregation phenomena within a bed composed of milli-metric size spherical beads rotated in a horizontal drum were investigated. The beads population was bi-dispersed, with two kinds of binary (half by half) compositions: a bi-size bed with two different sizes and a bi-density bed with two different densities. The distributions of the beads were observed optically on the front side of the bed by means of a lab-scale drum prototype. Different numbers and lengths of peripheral straight baffles were tested as well as different drum filling ratios. The photographical data were processed to obtain the front layer mechanical segregation index. This experimental index was compared to the simulated one, obtained by means of commercial discrete element software EDEM. The simulations were corroborated by the experiments provided that the friction coefficients of the discrete elements method (DEM) model were correctly adjusted. The global segregation index was also calculated from simulation data for all considered cases and its values were lower and less sensitive to baffles’ configurations than those for the front layer.
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Thomas, Ryan, and Andrew M. Lowy. "Models for pancreatic cancer: Giant steps forward, miles to go." Drug Discovery Today: Disease Models 2, no. 1 (March 2005): 27–33. http://dx.doi.org/10.1016/j.ddmod.2005.05.012.
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Sheldon-Keller, A. E., E. Lloyd-McGarvey, and R. J. Canterbury. "Assessing Organizational Effectiveness in Higher Education Drug Prevention Consortia." Journal of Drug Education 25, no. 3 (September 1995): 239–50. http://dx.doi.org/10.2190/q2h5-dfrj-yx38-jx53.
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Eighty-three consortia of institutions of higher education, organized under funding from the Fund for the Improvement of Post-Secondary Education (FIPSE) Drug Prevention Programs of the Department of Education, were surveyed to measure organizational effectiveness. Generalized satisfaction with the functioning of the consortia was related to the number of active members, the average miles traveled to meetings, satisfaction with performance of task functions, members' roles, the level of trust among members and the level of creativity and innovation in problem-solving. Satisfaction with goal attainment was significantly related to the presence of at least one “internal” goal for the consortium.
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Aresta, Antonella, Stefania De Santis, Alessia Carocci, Alexia Barbarossa, Andrea Ragusa, Nicoletta De Vietro, Maria Lisa Clodoveo, Filomena Corbo, and Carlo Zambonin. "Determination of Commercial Animal and Vegetable Milks’ Lipid Profile and Its Correlation with Cell Viability and Antioxidant Activity on Human Intestinal Caco-2 Cells." Molecules 26, no. 18 (September 17, 2021): 5645. http://dx.doi.org/10.3390/molecules26185645.
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Lipids from milk are important nutritional components, although their health effects, especially for animal milks, are still questioned. Four types of commercial milks, two semi-skimmed animal milks (bovine and goat) and two vegetable ones (soy and rice), along with their total and free lipid fractions recovered by sequential centrifugation or by ethyl acetate extraction, respectively, have been analyzed. A higher antioxidant ability, reported as Trolox equivalent antioxidant capacity, was found for all raw milks compared to that of rice. This trend was confirmed, except for soy milk, as ROS reduction in Caco-2 cells. The free lipid fraction was shown to have the highest antioxidant potential in both chemical and biological tests. Moreover, goat and soy raw milks positively regulated Caco-2 cell viability after an inflammatory stimulus. This effect was lost when their total lipid fraction was tested. Finally, only the free lipid fraction from rice milk preserved the Caco-2 viability after LPS stimulation. Our data demonstrated that the lipid profile of each milk, characterized by GC-MS analysis, could contribute to dictate its biological effects, and, although additional in vitro and in vivo studies are needed, they could support the literature re-evaluating the health effects of animal-based versus plant-based milks in the intestinal cellular model.
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Marfudhotun, Imas, and Wiyatmi Wiyatmi. "The Body Autonomy in the Short Story “Wanita Muda di Sebuah Hotel Mewah” by Hamsad Rangkuti: The Feminism Discourse Analysis of Sara Mills." International Journal of Linguistics, Literature and Translation 4, no. 10 (October 29, 2021): 38–45. http://dx.doi.org/10.32996/ijllt.2021.4.10.6.
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Patriarchal capitalism shows the dominance of men in the various life sector. Feminism, as a style, demands gender equality. This research aims to understand body autonomy in a short story "Wanita Muda di Sebuah Hotel Mewah" with Sara Mills' feminist perspective. This descriptive qualitative method took the data from the short story written by Hamsad Rangkuti in 2016, published by Senja. This research observed the subjects, objects, and readers via reading and note techniques. The results showed that the sixteen-year-old woman became the object. The woman did not have any autonomy over her body. The other problem was the economic problems that made her sold his virginity. The self-trafficking process of the hotel officer made the officer the subject. The third matter, the beauty of the body and the virginity, was the co-modification that had price value. The fourth, the woman could not control her body. The feminist interpretation, based on Sara Mills, in the short story, showed that the woman became the object, the guess, and the hotel officer as the subject. The position woman also had the reader's position, the hotel officer, and the hotel guest.
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Cooper, Hannah Luke Fenimore, Natalie D. Crawford, Regine Haardörfer, Nadya Prood, Carla Jones-Harrell, Umedjon Ibragimov, April M. Ballard, and April M. Young. "Using Web-Based Pin-Drop Maps to Capture Activity Spaces Among Young Adults Who Use Drugs in Rural Areas: Cross-Sectional Survey." JMIR Public Health and Surveillance 5, no. 4 (October 18, 2019): e13593. http://dx.doi.org/10.2196/13593.
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Background Epicenters of harmful drug use are expanding to US rural areas, with rural young adults bearing a disproportionate burden. A large body of work suggests that place characteristics (eg, spatial access to health services) shape vulnerability to drug-related harms among urban residents. Research on the role of place characteristics in shaping these harms among rural residents is nascent, as are methods of gathering place-based data. Objective We (1) analyzed whether young rural adults who used drugs answered self-administered Web-based mapping items about locations where they engaged in risk behaviors and (2) determined the precision of mapped locations. Methods Eligible individuals had to report recently using opioids to get high; be aged between 18 and 35 years; and live in the 5-county rural Appalachian Kentucky study area. We used targeted outreach and peer-referral methods to recruit participants. The survey asked participants to drop a pin in interactive maps to mark where they completed the survey, and where they had slept most; used drugs most; and had sex most in the past 6 months. Precision was assessed by (1) determining whether mapped locations were within 100 m of a structure and (2) calculating the Euclidean distance between the pin-drop home location and the street address where participants reported sleeping most often. Measures of central tendency and dispersion were calculated for all variables; distributions of missingness for mapping items and for the Euclidean distance variable were explored across participant characteristics. Results Of the 151 participants, 88.7% (134/151) completed all mapping items, and ≥92.1% (>139/151) dropped a pin at each of the 4 locations queried. Missingness did not vary across most participant characteristics, except that lower percentages of full-time workers and peer-recruited participants mapped some locations. Two-thirds of the pin-drop sex and drug use locations were less than 100 m from a structure, as were 92.1% (139/151) of pin-drop home locations. The median distance between the pin-drop and street-address home locations was 2.0 miles (25th percentile=0.8 miles; 75th percentile=5.5 miles); distances were shorter for high-school graduates, staff-recruited participants, and participants reporting no technical difficulties completing the survey. Conclusions Missingness for mapping items was low and unlikely to introduce bias, given that it varied across few participant characteristics. Precision results were mixed. In a rural study area of 1378 square miles, most pin-drop home addresses were near a structure; it is unsurprising that fewer drug and sex locations were near structures because most participants reported engaging in these activities outside at times. The error in pin-drop home locations, however, might be too large for some purposes. We offer several recommendations to strengthen future research, including gathering metadata on the extent to which participants zoom in on each map and recruiting participants via trusted staff.
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Thakarar, Kinna, Kim Murray, Nityasri Sankar, Jenny Carwile, F. L. Lucas, Debra D. Burris, Timothy J. Borelli, Robert Pinsky, Cheryl Liechty, and Robert P. Smith. "1418. Injections and Infections: Understanding Harm Reduction Utilization in a Rural State." Open Forum Infectious Diseases 7, Supplement_1 (October 1, 2020): S715—S716. http://dx.doi.org/10.1093/ofid/ofaa439.1600.
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Abstract Background Increasing rates of injection drug use (IDU) associated-infections suggest significant syringe service program (SSP) underutilization. Our study objective is to assess patient knowledge, attitudes, and practices of safe injection techniques and to determine predictors of SSP utilization in a rural state. Methods This is a fifteen-month cross-sectional study of participants hospitalized with IDU-associated infections at four hospitals in Maine. Data were collected through Audio Computer-Assisted Self-Interview survey and medical record review. Descriptive analyses were performed to characterize injection knowledge, attitudes and practices. The primary outcome was past 3-month SSP utilization, and the main independent variable was self-reported distance to SSP. Secondary outcomes were uptake of clean drug equipment, naloxone, and treatment with medication for opioid use disorder. Logistic regression analyses were performed to identify factors associated with the primary outcome, controlling for gender, homelessness, history of overdose, having primary care physician and distance to SSP. Results Of the 101 study participants, 62 participants (65%) reported past 3 month SSP utilization, though only 33% used SSPs frequently. Few participants (10%) reported clean needle/syringe use or clean drug equipment use (5%). Forty-eight percent of participants reported naloxone uptake, and 66% of participants were prescribed medication for opioid use disorder prior to admission. Many participants (59%) lived more than 10 miles from an SSP with 18% of participants living in rural areas. Fifty-four percent reported difficulty accessing an SSP. Participants who lived less than 10 miles of an SSP were more likely to use it (adjusted odds ratio 5.47; 95% CI 2.1- 14.3). Conclusion Our study highlights unsafe injection practices and lack of frequent SSP utilization among people admitted with IDU-associated infections in Maine. Especially given increasing stimulant use in our state and nationally, these results also highlight the need to promote harm reduction even among individuals prescribed medication for opioid use disorder. Particularly in rural areas where patients may live more than 10 miles from an SSP, expansion of harm reduction services should be a priority. Disclosures All Authors: No reported disclosures