scholarly journals MECHANOCHEMICAL METHOD OF PROCESSING SILICA-CONTAINING PLANT MATTER

2020 ◽  
pp. 255-261
Author(s):  
Tat'yana Petrovna Shcherbakova
Keyword(s):  
Plant Biomass ◽  
Acid Leaching ◽  
Target Component ◽  
Solid Residue ◽  
Plant Matter ◽  
Diffuse Halo ◽  
Bet Method ◽  
Pulsation Apparatus ◽  
Rotary Pulsation Apparatus ◽  
Biomass Loss

The possibility of complex processing of silica-containing plant biomass with the selection of a line of target products is investigated. The method includes the mechanochemical treatment of biomass in a solution of sodium hydroxide in a rotary pulsation apparatus at a temperature of self-heating not lower than 80 °C. The resulting suspension is separated on a solid residue and an extract. The solid residue is washed and dried to obtain pulp powder. The bio-filled silica gel with an SiO2 content of 49.4 wt.% to 62.6 wt.% is isolated from the extract after separation of the solid residue. By ashing the silicon-containing product at a temperature of 600 °C, amorphous silica is obtained. The content of SiO2 (as the target component) in the ash is 85.5–92.0%. The SiO2 diffraction pattern is characterized by the presence of a diffuse halo with a maximum at 2q=22.75 ° and the absence of diffraction peaks. Preliminary acid leaching can increase the purity of the resulting silica to 99.0%. The specific surface area of the obtained silica was determined by the BET method for nitrogen sorption at 260 m2/g. The effect of the concentration of the extractant on the yield of alkali-soluble substances and the degree of leaching of silicon was studied. It was shown that even at a 1% concentration of the extractant (NaOH), almost complete leaching of silicon from the plant matrix occurs. Depending on the increase in the concentration of NaOH, the degree of delignification of the biomass increases to 13–18–22%, respectively, with an increase in the concentration of NaOH 1–5–10%. Powdered cellulose was obtained with a content (%): silicon – 1.12, lignin – 34.8, alpha cellulose – 86.0, with a yield of 33.0% and a particle distribution of 80–300 μm. The amount of biomass loss is 17.6 wt.%.

Modernized structures of rotary-pulsation apparatus

2019 ◽  
pp. 3-6
Author(s):  
O.Yu. Erenkov ◽  
◽  
I.Ya. Lopushanskiy ◽  
E.V. Yavorskaya ◽  
◽  
...  
Keyword(s):  
Pulsation Apparatus ◽  
Rotary Pulsation Apparatus

scholarly journals Interannual Variation in Root Production in Grasslands Affected by Artificially Modified Amount of Rainfall

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Karel Fiala ◽  
Ivan Tůma ◽  
Petr Holub
Keyword(s):  
Interannual Variation ◽  
Plant Biomass ◽  
Growing Season ◽  
Lower Amount ◽  
Root Production ◽  
Climate Scenarios ◽  
Natural Rainfall ◽  
Plant Matter ◽  
Grassland Ecosystems ◽  
Below Ground

The effect of different amounts of rainfall on the below-ground plant biomass was studied in three grassland ecosystems. Responses of the lowland (dryFestucagrassland), highland (wetCirsiumgrassland), and mountain (Nardusgrassland) grasslands were studied during five years (2006–2010). A field experiment based on rainout shelters and gravity irrigation simulated three climate scenarios: rainfall reduced by 50% (dry), rainfall increased by 50% (wet), and the natural rainfall of the current growing season (ambient). The interannual variation in root increment and total below-ground biomass reflected the experimentally manipulated amount of precipitation and also the amount of current rainfall of individual years. The effect of year on these below-ground parameters was found significant in all studied grasslands. In comparison with dryFestucagrassland, better adapted to drought, submontane wetCirsiumgrassland was more sensitive to the different water inputs forming rather lower amount of below-ground plant matter at reduced precipitation.

scholarly journals Study of wheat straw delignification in a rotary-pulsation apparatus

2020 ◽  
pp. 103-110
Author(s):  
Larysa Sablii ◽  
Oleksandr Obodovych ◽  
Vitalii Sydorenko ◽  
Tamila Sheyko
Keyword(s):  
Wheat Straw ◽  
Production Technology ◽  
Raw Materials ◽  
Hydrolytic Enzymes ◽  
Bioethanol Production ◽  
Second Generation Bioethanol ◽  
Pulsation Apparatus ◽  
Rotary Pulsation Apparatus ◽  
Solid Water ◽  
Pre Treatment

This paper presents the results of studies of isolation lignin and hemicelluloses efficiency during the pre-treatment of wheat straw for hydrolysis in a rotary-pulsation apparatus. The pre-treatment of lignocellulosic raw materials for hydrolysis is a necessary step in the second-generation bioethanol production technology. The lignocellulose complex is destroyed during this process, and this allows hydrolytic enzymes access to the surface of cellulose fibers. The pre-treatment is the most energy-consuming stage in bioethanol production technology, since it usually occurs at high temperature and pressure for a significant time. One of the ways to improve the efficiency of this process is the use of energy-efficient equipment that allows intensifying heat and mass transfer. An example of such equipment is a rotary-pulsation apparatus, which are effective devices in stirring, homogenization, dispersion technologies, etc. The treatment of wheat straw in a rotary-pulsation apparatus was carried out under atmospheric pressure without external heat supply at solid/water ratios of 1:10 and 1:5 in the presence of alkali. It was determined that the treatment of the water dispersion of straw at ratio of 1:10 due to the energy dissipation during 70 minutes leads to the release of 42 % of lignin and 25.76 % of easily hydrolyzed polysaccharides. Changing the solid / water ratio from 1:10 to 1:5 leads to an increase in the yield of lignin and easily hydrolyzed polysaccharides to 58 and 33.38 %, respectively.

scholarly journals ABC Transporters Required for Hexose Uptake byClostridium phytofermentans

2019 ◽  
Vol 201 (15) ◽  
Author(s):  
Tristan Cerisy ◽  
Alba Iglesias ◽  
William Rostain ◽  
Magali Boutard ◽  
Christine Pelle ◽  
...  
Keyword(s):  
Abc Transporters ◽  
Extracellular Enzymes ◽  
Plant Biomass ◽  
Carbon Sources ◽  
Anaerobic Bacteria ◽  
Model Organism ◽  
Industrial Transformation ◽  
Content Type ◽  
Plant Matter

ABSTRACTThe mechanisms by which bacteria uptake solutes across the cell membrane broadly impact their cellular energetics. Here, we use functional genomic, genetic, and biophysical approaches to reveal howClostridium(Lachnoclostridium)phytofermentans, a model bacterium that ferments lignocellulosic biomass, uptakes plant hexoses using highly specific, nonredundant ATP-binding cassette (ABC) transporters. We analyze the transcription patterns of its 173 annotated sugar transporter genes to find those upregulated on specific carbon sources. Inactivation of these genes reveals that individual ABC transporters are required for uptake of hexoses and hexo-oligosaccharides and that distinct ABC transporters are used for oligosaccharides versus their constituent monomers. The thermodynamics of sugar binding shows that substrate specificity of these transporters is encoded by the extracellular solute-binding subunit. As sugars are not phosphorylated during ABC transport, we identify intracellular hexokinases based onin vitroactivities. These mechanisms used byClostridiato uptake plant hexoses are key to understanding soil and intestinal microbiomes and to engineer strains for industrial transformation of lignocellulose.IMPORTANCEPlant-fermentingClostridiaare anaerobic bacteria that recycle plant matter in soil and promote human health by fermenting dietary fiber in the intestine.Clostridiadegrade plant biomass using extracellular enzymes and then uptake the liberated sugars for fermentation. The main sugars in plant biomass are hexoses, and here, we identify how hexoses are taken in to the cell by the model organismClostridium phytofermentans. We show that this bacterium uptakes hexoses using a set of highly specific, nonredundant ABC transporters. Once in the cell, the hexoses are phosphorylated by intracellular hexokinases. This study provides insight into the functioning of abundant members of soil and intestinal microbiomes and identifies gene targets to engineer strains for industrial lignocellulosic fermentation.

scholarly journals An Improved Evaluation Strategy for Ash Analysis Using Scanning Electron Microscope Automated Mineralogy

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 484 ◽  
Author(s):  
Andrea C. Guhl ◽  
Valentin-G. Greb ◽  
Bernhard Schulz ◽  
Martin Bertau
Keyword(s):  
Sewage Sludge ◽  
Acid Leaching ◽  
Target Material ◽  
Analytical Techniques ◽  
Data Interpretation ◽  
Target Component ◽  
Sewage Sludge Ash ◽  
Phosphate Recovery ◽  
Automated Mineralogy ◽  
Sludge Ash

Sewage slush ashes are materials composed of polyphase particles. Ashes are fine-grained with many amorphous components, and analytical techniques such as X-ray diffractometry cannot recover all the properties. For sewage sludge ash, treatment often focuses on phosphate recovery. Automated mineralogy techniques were applied in order to study phosphate associations and their behavior towards chemical processes. This work shows the distribution of phosphate content in sewage sludge ash and identifies the main recovered phosphate phases in acid leaching. Data interpretation was focused on the target material, phosphate. The approach documents spectra labelling with respect to one target component, phosphorus. This is a tool for assessing sewage sludge ashes towards their phosphate recovery potential and highlights issues processing needs to address.

The Increase of Hydration Activity of Portland Cement by Additives of Crystalline Hydrates

2019 ◽  
Vol 974 ◽  
pp. 195-200
Author(s):  
Yury R. Krivoborodov ◽  
Svetlana V. Samchenko
Keyword(s):  
Phase Composition ◽  
Portland Cement ◽  
Cement Hydration ◽  
Bound Water ◽  
Cement Stone ◽  
Pulsation Apparatus ◽  
Rotary Pulsation Apparatus ◽  
Calcium Hydrosilicates ◽  
Crystalline Hydrates

The article presents the results of a study of the effect of synthesized microdisperse additives of crystalline hydrates based on calcium sulfoaluminates on the properties of cement stone. The effectiveness of the use of a rotary pulsation apparatus (RPA) to obtain microdispersed additives is identified. The possibility of accelerating the hardening of cement stone by entering microdispersed additives into its composition is shown. It has been established that in the presence of microdispersed additives of crystalline hydrates in the cement stone, the phase composition of hydrate tumors changes, the amount of calcium hydrosilicates and ettringite increases, the porosity decreases and the strength of the cement stone increases. This provision is confirmed by the increase in the degree of cement hydration, the amount of bound water in all periods of hardening of the stone. It is proposed to use microdisperse additives, which play the role of primers for the crystallization of ettringite and calcium hydrosilicates, to increase the strength of cement stone in the early stages of hardening.

scholarly journals Synergistic impacts of habitat loss and fragmentation on model ecosystems

2016 ◽  
Vol 283 (1839) ◽  
pp. 20161027 ◽  
Author(s):  
Lewis J. Bartlett ◽  
Tim Newbold ◽  
Drew W. Purves ◽  
Derek P. Tittensor ◽  
Michael B. J. Harfoot
Keyword(s):  
Land Use ◽  
Habitat Loss ◽  
Plant Biomass ◽  
Synergistic Effects ◽  
Ecosystem Model ◽  
Ecosystem Structure ◽  
Population Declines ◽  
Ecosystem Responses ◽  
Habitat Loss And Fragmentation ◽  
Biomass Loss

Habitat loss and fragmentation are major threats to biodiversity, yet separating their effects is challenging. We use a multi-trophic, trait-based, and spatially explicit general ecosystem model to examine the independent and synergistic effects of these processes on ecosystem structure. We manipulated habitat by removing plant biomass in varying spatial extents, intensities, and configurations. We found that emergent synergistic interactions of loss and fragmentation are major determinants of ecosystem response, including population declines and trophic pyramid shifts. Furthermore, trait-mediated interactions, such as a disproportionate sensitivity of large-sized organisms to fragmentation, produce significant effects in shaping responses. We also show that top-down regulation mitigates the effects of land use on plant biomass loss, suggesting that models lacking these interactions—including most carbon stock models—may not adequately capture land-use change impacts. Our results have important implications for understanding ecosystem responses to environmental change, and assessing the impacts of habitat fragmentation.

scholarly journals The mechanochemical treatment of the building materials

2015 ◽  
Vol 3 ◽  
pp. 22-25
Author(s):  
Gurinovich L.S. ◽  
Usov B.A.
Keyword(s):  
Building Materials ◽  
Mechanochemical Treatment ◽  
Labor Costs ◽  
Activation Time ◽  
Technological Parameters ◽  
Chemical Additives ◽  
Distinctive Features ◽  
Pulsation Apparatus ◽  
Rotary Pulsation Apparatus ◽  
Strength And Durability

The article is devoted to the obtaining of activated additives and cements, to improve the quality or the obtaining of new building materials using rotary pulsation apparatus (RPA). It also considers the efficiency of the RPA. As a result the works were obtained in different activated in the RPA chemical additives for concrete from sparingly soluble in water products established distinctive features of the solutions of plasticizers and complex additives, treated in the RPA. It is shown that the preparation of concrete with the use of activated materials in the RPA to reduce labor costs in the manufacture of a product, reduce the consumption of cement, flow additives, plasticizers, water consumption, accelerate hardening and to increase strength and durability of concrete. It is noted that when changing the amount of additives in the solution and time of mechanochemical treatment, it becomes possible to control the technological parameters of concrete mixture (mobility, stiffness) and thus increase the strength of concrete. When the content of additives PDO 0.15% and activation time of 5 minutes the increase in strength was 60 kg/cm2. With increasing number of activated additives up to 1 % strength in concrete was increased, while the introduction of the same amount of additives without activation promoted a decrease in strength below without additional values.

scholarly journals Effect of modifiers and mineral additives from industrial waste on the quality of aerated concrete products

Technobius ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 0010
Author(s):  
Yerlan Sabitov ◽  
Duman Dyussembinov ◽  
Daniyar Bazarbayev
Keyword(s):  
Fly Ash ◽  
Polyvinyl Acetate ◽  
Raw Materials ◽  
Capillary Suction ◽  
Pulsation Apparatus ◽  
Rotary Pulsation Apparatus ◽  
Aerated Concrete ◽  
The Given ◽  
Mineral Additives

The given article is devoted to research of influence of polymer modifiers and mineral additives on quality of composite aerated concrete products. When selecting the composition of composite aerated concrete local raw materials and components were used: portland cement, sand, aluminum powder, polyvinyl acetate, fly ash, post-alcoholic bard and whey of milk. Preliminary polyvinyl acetate was combined with binder mixing water at a temperature above 55ºC to obtain a readily soluble polymer emulsion. Dispersion was carried out with a rotary-pulsation apparatus at a pressure of 0.5-1.0 MPa and a rotor speed of ~1200 rpm. In the same apparatus the complex modifier was produced. The offered technology of production of a complex modifier seems to be the most effective for composite aerated concrete. It made it possible to reduce water absorption and capillary suction of composite aerated concrete by an average of 25% and 45%, respectively. Moreover, different combinations of fly ash, polymer and modifier made it possible to achieve optimal values of thermal conductivity, compressive strength and frost resistance of composite aerated concrete.

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