scholarly journals Technological evaluation of bentonite suspension obtained using hydromechanical method

2021 ◽  
pp. 299-304
Author(s):  
А.В. Сильвестров ◽  
В.А. Загоруйко ◽  
Н.Б. Чаплыгина ◽  
В.В. Рыжков ◽  
М.В. Ермихина ◽  
...  

Изучены физико-химические свойства суспензии бентонита, полученной гидромеханическим способом в сравнении с традиционным. Представлены результаты исследований по обеспечению стабильности винодельческой продукции против необратимых коллоидных помутнений при применении суспензии бентонита, приготовленной гидромеханическим способом. Установлено, что суспензия бентонита, приготовленная гидродинамическим способом при частоте вращения ротора 2980 об/мин. в течение 5 мин. и средним размером частиц от 8 до 10 мкм, позволяет значительно повысить качество обработки виноматериалов и достичь высоких показателей их стабильности, а также снизить объем образующихся осадков до 10 процентов. Результаты технологической оценки суспензии бентонита, полученной на экспериментальной установке, положены в основу определения режимных и конструктивных параметров оборудования для приготовления растворов и суспензий вспомогательных материалов в виноделии. Physicochemical properties of bentonite suspension obtained using hydromechanical method in comparison with traditional one have been studied. The results of studies on providing the wine product stability against nonreversible colloidal haze in applying bentonite suspension prepared using hydromechanical method are presented. It was found that bentonite suspension prepared using hydrodynamic method at a rotor speed of 2980 rpm during 5 minutes and an average particle size of 8 to 10 µm, can significantly improve the quality of processing base wines, achieve high stability level and reduce the amount of sediment by up to 10 percent. The results of technological evaluation of bentonite suspension obtained using experimental unit are the basis for determining the operating and design parameters of equipment for preparation of solutions and suspensions of auxiliary materials in winemaking.

2009 ◽  
Vol 421-422 ◽  
pp. 269-272
Author(s):  
Takashi Kubo ◽  
Masayuki Hogiri ◽  
Hiroshi Kagata ◽  
Atsushi Nakahira

Nano-sized BaTiO3 powders with narrow size distribution and the high tetragonality were attempted to synthesize by the rotary-hydrothermal process in water system, using two kinds of commercial anatase-type TiO2 (ST21/ST01) with different particle size and Ba(OH)2. The rotary-hydrothermal syntheses were done with the rotary-speed of 20 revolutions per minute at 523 K for 24 h. Highly- and mono-dispersed BaTiO3 powders were successfully synthesized by applying the rotary-hydrothermal process. For rotary-hydrothermal synthesis, it was found that the average size, tetragonality, and quality of the BaTiO3 particle strongly depended on the particle size of the starting material. In the case of using ST01 as a starting material, BaTiO3 nano-powders mainly composed of coarse-faceted particles (average particle size = ca.100 nm) with the tetragonal phase and very little lattice defects were successfully synthesized.


2021 ◽  
Vol 296 ◽  
pp. 07012
Author(s):  
Nataliya Lesnikova ◽  
Olga Chugunova ◽  
Valentina Lapina ◽  
Tatiana Kotova ◽  
Ekaterina Pastushkova

The study focuses on obtaining the finely ground wheat germ flour mix by employing dry mechanical activation. During the study, wheat germ is ground using DESI-11 disintegrator and mechanically activated in PM-10 centrifugal mill with the rotor speed of 1050 rpm. According to the study findings, the finely ground wheat germ flour mix obtained by dry mechanical activation possesses increased bulk density and improved water absorption capacity when compared to the product obtained from wheat germ without mechanical activation applied. The average particle size is reduced from 114 μm to 52 μm. The study findings indicate that obtaining the finely ground wheat germ flour mix by dry mechanical activation prevents the occurrence of the caking effect as well as improves the quality of baked products.


2013 ◽  
Vol 833 ◽  
pp. 335-338
Author(s):  
Zhen Wu ◽  
Chong Zhe Zhong ◽  
Yu Song ◽  
Ying Qiang Zhang

Polyacrylate emulsions (PAs) with core-shell structure were prepared by semi-continuous emulsion polymerization with diacetone acrylamide (DAAM) and adipic dihydrazide (ADH) as crosslinkable monomers and compound emulsifier system of SDS/0P-21/MS-1, reactive emulsifier NRS-10 as emulsifier respectively. The polyacrylate emulsion with keto-hydrazide crosslinking was characterized by Fourier transform infrared spectroscopy (FTIR), FTIR analyses demonstrated that the keto-hydrazide crosslinking reaction occur in the emulsion. The properties of both emulsions and films were tested by size analysis, viscosity analysis and others. The results showed that the average particle size with reactive emulsifier system of around 93 nm, coagulation rate of around 0.81% and water absorption rate of around 6.7% and the quality of polyacrylate emulsion with reactive emulsifier system was excellent.


Author(s):  
S. Postelga ◽  

The purpose of research: a comprehensive assessment of self-propelled mixer-dispenser Siloking SelfLine 4.0 Premium 2215 during operation. Research methods: establishment of design features of the mixer-dispenser was performed by the survey method of the sample submitted for testing, quality indicators of the machine were evaluated by standardized methods: quality of technological process according to GSTU 46.008, operational-technological indicators according to DSTU 8424, energy indicators according to SOU 74.3-37 -04604309-824, economic indicators according to DSTU 4397, indicators of safety and ergonomics according to KD 46.16.02.03, SOU 74.3-37-133. Research result.: During the mixing of 5 types of feed, a high-quality homogeneous feed mixture was obtained, the moisture content of which was 59.5%, the bulk density was 405 kg / m3, and the average particle size was 17.4 mm. The uniformity of feed mixing was 94.3 %, and the uniformity of feed distribution was 95.5 %. The degree of grinding of stem fodder was 1.4 times (for hay). The test results show that the mixer-dispenser satisfactorily and efficiently performs the specified process. The feed monolith is preserved after passing the cutting drum, no looseness of the feed slice is detected. Returned losses at the bottom of the silo do not exceed 1 %. The productivity of the mixer-dispenser for the technological process of loading, transportation, mixing and distribution of feed on a dairy farm with a population of 1600 heads is 10.6 t / h, the average productivity of feed loading is 28.6 t / h. (including silage -41 t / h; haylage 43.4 t / h), feed distribution capacity −116 t / h. Specific fuel consumption is 1.2 liters per ton of loaded, crushed, mixed and distributed feed. Labor costs for the implementation of the technological process is 0.09 man-hours / t, direct operating costs -91 UAH / t. Conclusions. Self-propelled mixer-dispenser Siloking SelfLine 4.0 Premium 2215 is a multifunctional machine that allows, with the involvement of only one operator, to ensure self-loading of components, preparation and distribution of quality feed to animals at a given diet. During self-loading the error of dosing of components by the mixer-distributor does not exceed 0,5% that allows to prepare a forage mix close to settlement. The self-loading milling working mechanism of the mixer-distributor provides an equal cut of a monolith of silage and haylage that allows to keep quality of consolidation and prevents losses of nutritiousness and power value of a forage. Self-propelled mixer-distributor is characterized by 1.5 - 2.1 times higher than trailed mixer-distributors productivity of the process as a whole, has a high enough productivity of self-loading components and distribution of feed, minimizes specific labor costs and fuel consumption per 1 tons of cooked and distributed feed.


MRS Advances ◽  
2020 ◽  
Vol 5 (57-58) ◽  
pp. 2961-2972
Author(s):  
P.C. Meléndez-González ◽  
E. Garza-Duran ◽  
J.C. Martínez-Loyola ◽  
P. Quintana-Owen ◽  
I.L. Alonso-Lemus ◽  
...  

In this work, low-Pt content nanocatalysts (≈ 5 wt. %) supported on Hollow Carbon Spheres (HCS) were synthesized by two routes: i) colloidal conventional polyol, and ii) surfactant-free Bromide Anion Exchange (BAE). The nanocatalysts were labelled as Pt/HCS-P and Pt/HCS-B for polyol and BAE, respectively. The physicochemical characterization of the nanocatalysts showed that by following both methods, a good control of chemical composition was achieved, obtaining in addition well dispersed nanoparticles of less than 3 nm TEM average particle size (d) on the HCS. Pt/HCS-B contained more Pt0 species than Pt/HCS-P, an effect of the synthesis method. In addition, the structure of the HCS remains more ordered after BAE synthesis, compared to polyol. Regarding the catalytic activity for the Oxygen Reduction Reaction (ORR) in 0.5 M KOH, Pt/HCS-P and Pt/HCS-B showed a similar performance in terms of current density (j) at 0.9 V vs. RHE than the benchmark commercial 20 wt. % Pt/C. However, Pt/HCS-P and Pt/HCS-B demonstrated a 6 and 5-fold increase in mass catalytic activity compared to Pt/C, respectively. A positive effect of the high specific surface area of the HCS and its interactions with metal nanoparticles and electrolyte, which promoted the mass transfer, increased the performance of Pt/HCS-P and Pt/HCS-B. The high catalytic activity showed by Pt/HCS-B and Pt/HCS-P for the ORR, even with a low-Pt content, make them promising cathode nanocatalysts for Anion Exchange Membrane Fuel Cells (AEMFC).


2002 ◽  
Vol 721 ◽  
Author(s):  
Monica Sorescu

AbstractWe propose a two-lattice method for direct determination of the recoilless fraction using a single room-temperature transmission Mössbauer measurement. The method is first demonstrated for the case of iron and metallic glass two-foil system and is next generalized for the case of physical mixtures of two powders. We further apply this method to determine the recoilless fraction of hematite and magnetite particles. Finally, we provide direct measurement of the recoilless fraction in nanohematite and nanomagnetite with an average particle size of 19 nm.


1970 ◽  
Vol 26 (1) ◽  
pp. 16 ◽  
Author(s):  
S Balasubramanian ◽  
Rajkumar Rajkumar ◽  
K K Singh

Experiment to identify ambient grinding conditions and energy consumed was conducted for fenugreek. Fenugreek seeds at three moisture content (5.1%, 11.5% and 17.3%, d.b.) were ground using a micro pulverizer hammer mill with different grinding screen openings (0.5, 1.0 and 1.5 mm) and feed rate (8, 16 and 24 kg h-1) at 3000 rpm. Physical properties of fenugreek seeds were also determined. Specific energy consumptions were found to decrease from 204.67 to 23.09 kJ kg-1 for increasing levels of feed rate and grinder screen openings. On the other hand specific energy consumption increased with increasing moisture content. The highest specific energy consumption was recorded for 17.3% moisture content and 8 kg h-1 feed rate with 0.5 mm screen opening. Average particle size decreased from 1.06 to 0.39 mm with increase of moisture content and grinder screen opening. It has been observed that the average particle size was minimum at 0.5 mm screen opening and 8 kg h-1 feed rate at lower moisture content. Bond’s work index and Kick’s constant were found to increase from 8.97 to 950.92 kWh kg-1 and 0.932 to 78.851 kWh kg-1 with the increase of moisture content, feed rate and grinder screen opening, respectively. Size reduction ratio and grinding effectiveness of fenugreek seed were found to decrease from 4.11 to 1.61 and 0.0118 to 0.0018 with the increase of moisture content, feed rate and grinder screen opening, respectively. The loose and compact bulk densities varied from 219.2 to 719.4 kg m-3 and 137.3 to 736.2 kg m-3, respectively.  


Author(s):  
И.В. Бачериков ◽  
Б.М. Локштанов

При проектировании открытых и закрытых хранилищ измельченных сыпучих материалов древесных материалов, таких как щепа и опилки, большое значение имеет угол естественного откоса (статический и динамический) этих материалов. В технической литературе приводятся противоречивые сведения о величине этих углов, что приводит к ошибкам при проектировании складов. В справочных данных не учитываются условия, в которых эксплуатируются емкости для хранения сыпучих материалов, свойства и состояние этих сыпучих материалов. В свою очередь, ошибки при проектировании приводят к проблемам (зависание, сводообразование, «затопление» и т. д.) и авариям при эксплуатации бункеров и силосов на производстве. В статье представлены сведения, посвященные влиянию влажности и температуры на угол естественного откоса сыпучих материалов. На основании лабораторных и натурных экспериментов, проведенных с помощью специально разработанных методик и установок, была скорректирована формула для определения углов естественного откоса (статического и динамического) для измельченных древесных материалов в зависимости от их фракционного и породного состава, влажности (абсолютной и относительной) и температуры. При помощи скорректированной формулы можно определить угол естественного откоса древесных сыпучих материалов со среднегеометрическим размером частицы от 0,5 мм до 15 мм (от древесной пыли до технологической щепы) в различных производственных условиях. Статья может быть полезна проектировщикам при расчете угла наклона граней выпускающей воронки бункеров и силосов предприятий лесной отрасли и целлюлозо-бумажной промышленности. In the design of open and closed storage warehouses chopped wood materials for bulk materials such as wood chips and sawdust, great importance has an angle of repose (static and dynamic) of these materials. In the technical literature are conflicting reports about the magnitude of these angles, which leads to errors in the design of warehouses. In the referencesdoes not take into account the conditions under which operated capacities for storage of bulk materials, and properties and condition of the bulk material. The design errors lead to problems (hanging, arching, «flooding», etc.) and accidents in the operation of hoppers and silos at the mills. The article provides information on the impact of humidity and temperature on the angle of repose of granular materials. On the basis of laboratory and field experiments, conducted with the help of specially developed techniques and facilities has been adjusted formula for determining the angle of repose (static and dynamic) for the shredded wood materials depending on their fractional and species composition, humidity (absolute and relative) and temperature. It is possible, by using the corrected formula, to determine the angle of repose of loose wood materials with average particle size of from 0.5 mm to 15 mm (wood dust to pulpchips) in various operating conditions. The article can be helpful to designers in the calculation of the angle of inclination of the funnel faces produces bunkers and silos forest industries and pulp and paper industry.


2020 ◽  
Vol 27 (22) ◽  
pp. 3623-3656 ◽  
Author(s):  
Bruno Fonseca-Santos ◽  
Patrícia Bento Silva ◽  
Roberta Balansin Rigon ◽  
Mariana Rillo Sato ◽  
Marlus Chorilli

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.


2020 ◽  
Vol 17 ◽  
Author(s):  
Mohammad Hossain Shariare ◽  
Tonmoy Kumar Mondal ◽  
Hani Alothaid ◽  
Md. Didaruzzaman Sohel ◽  
MD Wadud ◽  
...  

Aim: EPAS (evaporative precipitation into aqueous solution) was used in the current studies to prepare azithromycin nanosuspensions and investigate the physicochemical characteristics for the nanosuspension batches with the aim of enhancing the dissolution rate of the nanopreparation to improve bioavailability. Methods: EPAS method used in this study for preparing azithromycin nanosuspension was achieved through developing an in-house instrumentation method. Particle size distribution was measured using Zetasizer Nano S without sample dilution. Dissolved azithromycin nanosuspensions were also compared with raw azithromycin powder and commercially available products. Total drug content of nanosuspension batches were measured using an Ultra-Performance Liquid Chromatography (UPLC) system with Photodiode Array (PDA) detector while residual solvent was measured using gas chromatography (GC). Results: The average particle size of azithromycin nanosuspension was 447.2 nm and total drug content was measured to be 97.81% upon recovery. Dissolution study data showed significant increase in dissolution rate for nanosuspension batch when compared to raw azithromycin and commercial version (microsuspension). The residual solvent found for azithromycin nanosuspension is 0.000098023 mg/ mL or 98.023 ppb. Conclusion: EPAS was successfully used to prepare azithromycin nanoparticles that exhibited significantly enhanced dissolution rate. Further studies are required to scale up the process and determine long term stability of the nanoparticles.


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