scholarly journals The Influence of Selected Properties of Particles in the Jigging Process of Aggregates on an Example of Chalcedonite

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 600 ◽  
Author(s):  
Agnieszka Surowiak ◽  
Tomasz Gawenda ◽  
Agata Stempkowska ◽  
Tomasz Niedoba ◽  
Alona Nad
Keyword(s):  
Particle Density ◽  
Size Fraction ◽  
Chemical Properties ◽  
Geometric Properties ◽  
Research Goal ◽  
Polymorphic Forms ◽  
Particle Shapes ◽  
Separation Product ◽  
Dynamic Shape ◽  
Selection Of

The influence of the physical, geometric and chemical properties of particles on the results of aggregate separation by means of a laboratory ring jig is presented in this paper. The experiment was based on separation of chalcedonite particles in a narrow particle size fraction composed separately of regular and irregular particles, which was prepared in accordance with patent inventions. On its basis, the geometric properties—projection diameter and (volumetric and dynamic) shape coefficients—as well as physical properties—particle density—were determined in products of the regular and irregular particles. The terminal settling velocities of the regular and irregular particles were calculated for a randomly selected sample of particles in each obtained separation product. The statistical analysis of the geometric properties of the particles allowed to evaluate the influence of these parameters on aggregate processing with respect to selection of particles homogenous in terms of their shapes. The comparison of the particle shapes’ influence on the chalcedonite feed separation effects was made by the means of the values of the shape coefficients: the dynamic and volumetric ones. Additionally, tests were carried out using Raman spectroscopy in order to determine the mechanisms of density change in the aggregate. The research goal was realised through detecting and analysing the polymorphic forms of the silica and allogenic minerals precipitated on the surface and inside the chalcedonite particles.

Depletion of coating color components in the blade coating process circulation

TAPPI Journal ◽  
2011 ◽  
Vol 10 (9) ◽  
pp. 17-23 ◽  
Author(s):  
ANNE RUTANEN ◽  
MARTTI TOIVAKKA
Keyword(s):  
Fine Particles ◽  
Particle Density ◽  
Stable Process ◽  
Size Fraction ◽  
Color Stability ◽  
Strong Interactions ◽  
Coating Process ◽  
Size Segregation ◽  
Coating Color ◽  
Average Size

Coating color stability, as defined by changes in its solid particle fraction, is important for runnability, quality, and costs of a paper coating operation. This study sought to determine whether the size or density of particles is important in size segregation in a pigment coating process. We used a laboratory coater to study changes in coating color composition during coating operations. The results suggest that size segregation occurs for high and low density particles. Regardless of the particle density, the fine particle size fraction (<0.2 μm) was the most prone for depletion, causing an increase in the average size of the particles. Strong interactions between the fine particles and other components also were associated with a low depletion tendency of fine particles. A stable process and improved efficiency of fine particles and binders can be achieved by controlling the depletion of fine particles.

scholarly journals Insights in Behavior of Variably Formulated Alginate-Based Microcapsules for Cell Transplantation

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Pia Montanucci ◽  
Silvia Terenzi ◽  
Claudio Santi ◽  
Ilaria Pennoni ◽  
Vittorio Bini ◽  
...  
Keyword(s):  
Divalent Cations ◽  
Chemical Properties ◽  
Live Cells ◽  
High Performing ◽  
Physical Chemical ◽  
Degenerative Disorders ◽  
Selection Of ◽  
Better Than

Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation,in vitroandin vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules’ basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others.

scholarly journals METHOD FOR IDENTIFYING SUITABLE COMPONENTS FOR FUNCTIONAL INTEGRATION – FOCUSING ON GEOMETRIC CHARACTERISTICS

2021 ◽  
Vol 1 ◽  
pp. 2047-2056
Author(s):  
Michael P. Voigt ◽  
Dominik Klaiber ◽  
Patrick Hommel ◽  
Daniel Roth ◽  
Hansgeorg Binz ◽  
...  
Keyword(s):  
Lightweight Design ◽  
Functional Integration ◽  
Resource Efficiency ◽  
Installation Space ◽  
Geometric Properties ◽  
Geometric Characteristics ◽  
Step Procedure ◽  
Cad Models ◽  
Selection Of

AbstractThe approach of functional integration has the potential to solve challenges regarding lightweight design and resource efficiency since the number of parts and therefore the weight and needed installation space can be reduced. One important step in developing integrative concepts is the pre-selection of suitable functions or components. Previous methods of pre-selection take various aspects into account. However, pre-selection based on these methods usually requires additional tables and forms, whose preparation and editing quickly becomes time-consuming. At the same time, most of the development engineers are working on CAD models. However, their use in the selection of suitable integration partners is not yet supported sufficiently. The development of more than 80 concepts on five different vehicles has shown that the consideration of geometric properties (position, orientation, size) is effective, as they can be identified with minimal analysis effort while working on CAD. In this paper a four-step procedure is presented how integration partners can be identified directly on the basis of CAD models. A following evaluation with development engineers in practice completes the research.

scholarly journals Physical and chemical properties of soils in different physiographic environments in the southern Amazonas region

2019 ◽  
Vol 35 (4) ◽  
Author(s):  
Willian Barros Nascimento ◽  
Milton César Costa Campos ◽  
Bruno Campos Mantovanelli ◽  
Luís Antônio Coutrim dos Santos ◽  
José Mauricio Cunha ◽  
...  
Keyword(s):  
Particle Density ◽  
Broad Class ◽  
Chemical Properties ◽  
Principal Component ◽  
Available Phosphorus ◽  
Physical And Chemical Properties ◽  
Dry Land ◽  
Chemical Properties Of Soils ◽  
Physical And Chemical ◽  
And Chemical Properties

The Amazon region has a great diversity of landscapes such as forests galleries, natural fields (“Cerrados Amazônicos”), dense forest, these environments made possible the formation of a broad class of soils over time. The aim of this study was to evaluate the physical and chemical properties of soils in different physiographic environments in southern Amazonas, Brazil. Three areas of representative physiographies were selected, all of them in natural conditions: natural field / forest and floodplain / dry land transitions, and corrugated relief areas. Soil samples were collected in layers of 0.0 to 0.20 and 0.80-1.0 m. From the samples collected the following physical analyzes were performed: particle size, bulk density, particle density, total porosity and saturated hydraulic conductivity; and chemical: exchangeable calcium, magnesium, aluminum and potassium available, phosphorus, potential acidity, pH and organic carbon. Based on the results of chemical analysis were calculated the sum of bases and base saturation. The results were submitted to multivariate statistics analysis, at the discretion of the principal component analysis (PCA). From the results it is clear that different physiographic environments studied influence the formation of different soil classes, featuring the diversity of Amazonian soils. The PCA allowed the distinction and formation of different similarity groups, thus enabling to relate the physical and chemical properties with the physiographic formation in which they are inserted.

Soil fertility and leaf nutrient status of litchi orchard sites

2021 ◽  
Vol 30 (2) ◽  
pp. 141-149
Author(s):  
Tasnim Zannat ◽  
Farhana Firoz Meem ◽  
Rubaiat Sharmin Promi ◽  
Umme Qulsum Poppy ◽  
MK Rahman
Keyword(s):  
Particle Density ◽  
Organic Matter Content ◽  
Chemical Properties ◽  
Nutrient Status ◽  
Matter Content ◽  
Average Particle ◽  
Total N ◽  
Available N ◽  
Dominant Soil ◽  
Physico Chemical

Twelve soil and twelve leaf samples were collected from twelve litchi (Litchi chinensis Sonn.) orchards from different locations of Dinajpur to evaluate some physico-chemical properties and nutrient status of soil, and concentration of nutrients in litchi leaf. The pH of the soil varied from very strong acidic to medium acidic (4.8 - 5.7), organic matter content varied from 0.84 - 1.88%, EC varied from 302.4 - 310.2 μS/cm. The dominant soil textural class was clay loam. The average particle density was 2.49g/cm3. Total N, P, K and S in soils were 0.053 - 0.180%, 0.02 - 0.07%, 0.046 - 0.370 meq/100 g, and 0.015 - 0.028%, respectively. Available N, P, K, S, Zn, Fe, Mn and B in soils 30.40 - 57.8 mg/kg, 10.53 - 14.33 mg/kg, 0.03 - 0.32 meq/100 g, 20.03-34.80 mg/kg, 0.68-1.50 μg/g, 31.8 - 41.5 μg/g, 6.75 - 7.39 μg/g and 0.25-0.51 μg/g, respectively. The concentration of total N, P, K, S, Zn and Mn in the leaf were 1.74 - 2.20%, 0.11 - 0.188%, 0.104- 0.198%, 0.129 - 0.430%, 12 - 14 μg/g and 30 - 74 μg/g, respectively. The overall results indicated that the fertility status of the soils under the litchi plantation in the Dinajpur area are medium fertile. So, farmers could be advised to grow litchi plants after applying amendments to the soils to improve the physico-chemical properties in the Dinajpur area of Bangladesh. Dhaka Univ. J. Biol. Sci. 30(2): 141-149, 2021 (July)

Parameter selection of Polystyrene-Dietilenetriaminepenta acetate Resin Synthesis for the separation of rare Earth Elements by using Plackett-Burman Experimental Design

2021 ◽  
pp. 5629-5634
Author(s):  
Herman Herman ◽  
Bohari Yusuf ◽  
Laode Rijai ◽  
Hadi Kuncoro ◽  
Anni Anggraeni ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Chemical Properties ◽  
Ammonia Concentration ◽  
Yield Ratio ◽  
Scale Production ◽  
Separation And Purification ◽  
Diethylene Triamine ◽  
Stirring Rate ◽  
Volume Reaction ◽  
Selection Of

The development of the separation method has an essential role in developing science and technology for the separation and purification of an element or compound from other mixtures based on differences in physical and chemical properties. This research is more focused on the selection parameters of polystyrene-based resin production using diethylene triamine penta-acetate (DTPA) light, which used as a prototype for improved scale production. The Plackett-Burman design was used to select variables that have significant influence in Methylaminopolystyrene-Diethylenetriaminepentaacetate (MAP-DTPA) resin synthesis. Eleven variables such as mol ratio of Methylamino Polystyrene and diethylene triamine penta-acetate ligands, solvent volume, reaction time, stirring rate, reaction temperature, total volume, reaction pH, incubation time, ammonia concentration, and the addition of methanol were carried out for the selection of parameters or variables in the process of MAP-DTPA resin synthesis through a statistical approach in studies for design experiments using Software Design Expert 9.0.6.2. Of the eleven variables in resin synthesis obtained, six variables have a positive influence on the yield ratio value (percent yield ratio) of MAP-DTPA resin are the mol ratio of MAP and DTPA, Stirring Rate, reaction temperature, total volume, degree of acidity, and ammonia concentration.

scholarly journals Assessment of Lake Sediments Properties and Contaminations Level

2012 ◽  
Vol 610-613 ◽  
pp. 2100-2103
Author(s):  
Nik Norsyahariati Nik Daud ◽  
Nur Safrah Anuar ◽  
Zainuddin Yusoff ◽  
Amimul Ahsan
Keyword(s):  
Specific Surface ◽  
Concentration Level ◽  
Sediment Quality ◽  
Size Fraction ◽  
Chemical Properties ◽  
Sediment Concentration ◽  
Contamination Level ◽  
Contaminant Concentration ◽  
Quality Guidelines ◽  
Academic Buildings

Sediments are principal carriers of the trace elements in the hydrosphere. Properties of the sediment (such as grain size, specific surface area and pore volume) decide the concentration level of the pollutant contain in water. The properties of sediment differed in each lake according to the normal geological phenomenon and source of discharge wastewater. The purpose of this study is to investigate the properties and contamination level of the sediment collected from lakes in Universiti Putra Malaysia (UPM). Sediment samples are taken from three different lakes; Lake IT, Lake ENG and Lake PK. These locations are selected due to the type of wastewater has been discharged into the lakes which are from colleges and academic buildings. The sediments were tested in terms of physical, chemical properties and contaminant concentration (Pb, P and Cu). Using the contaminant concentration results; the sediment concentration level of the pollutant of each lakes were referred to the Consensus- Based Sediment Quality Guidelines (CBSQG-2003). The dominant grain sizes of the sediments were found in the range of silt/clay; with the size fraction in the range 12.74% to 12.83%. The specific surface areas of sediments were in the range of 16.3 to 22.5 m2/g with a pore size distribution in the range of 20 to 29 mm3/g. The chemical properties show that the pH values are in normal range; pH 7, TOC values in the range of 10.84 to 12.39% and salinity values in the range of 0.05 to 0.06 dS/m. The contaminant concentrations show that the main heavy metal presents in Lake IT, Lake ENG and Lake PK as Lead (Pb) with 0.033 mg/l, 0.036 mg/L and 0.038 mg/L, respectively. According to the CBSQG-2003, due to the concentration of Lead presents in lakes sediment in UPM area, the sediments were categorised as non-polluted.

Improving water use of annual crops and pastures—limitations and opportunities in Western Australia

2001 ◽  
Vol 52 (2) ◽  
pp. 171 ◽  
Author(s):  
David Tennant ◽  
David Tennant ◽  
David Hall ◽  
David Hall
Keyword(s):  
Water Use ◽  
Western Australia ◽  
Chemical Properties ◽  
Farming Systems ◽  
Water Infiltration ◽  
Root Penetration ◽  
Depth Limit ◽  
Annual Crops ◽  
Loamy Sand Soil ◽  
Selection Of

As part of a wider analysis of the potential role for lucerne in farming systems being developed for containing the spread of salinisation, we have reviewed information generated in Western Australia on opportunities for improving the water use of annual crops and pastures. Substantial increases in water use have been shown to be possible in a number of situations and rainfall environments. Best gains, of the order of 40–70 mm, were reported on deep sand and loamy sand soil types. These were achieved from selection of deep-rooted and longer growing crop and pasture species, and from amelioration of widespread traffic pans and subsoil acidity, and/or selection of tolerant species. On more widespread gradational and duplex soils, soil physical and chemical properties that restrict water infiltration and/or root penetration to depth limit the potential to increase water use. Increases in production and water use are still possible, depending on the permeability of the lower horizons of these soils and on rainfall distribution. At best, recorded increases on these soils were of the order of 5–15 mm in short season, low rainfall environments, and around 40 mm in long season, high rainfall environments. These increases in water use were not invariable. Increases in water use were not noted in dry years on all soils and in all years on shallow duplex soils with impermeable B horizons. Seasonality impacts on all outcomes and is a key issue on all soils and in all rainfall environments.

Identifying ecological barriers to restoration in temperate grassy woodlands: soil changes associated with different degradation states

2002 ◽  
Vol 50 (6) ◽  
pp. 699 ◽  
Author(s):  
Suzanne M. Prober ◽  
Kevin R. Thiele ◽  
Ian D. Lunt
Keyword(s):  
Chemical Properties ◽  
Soil Conditions ◽  
Reference Sites ◽  
Ecosystem Recovery ◽  
Positive Feedbacks ◽  
Ecological Barriers ◽  
Eastern Australia ◽  
Repeated Pattern ◽  
Agricultural Regions ◽  
Selection Of

Temperate grassy woodlands were once the dominant vegetation across many agricultural regions of south-eastern Australia, but most of these are now highly degraded and fragmented. Adequate conservation of these woodlands is dependent on successful ecological restoration; however, ecological barriers often limit ecosystem recovery once degrading processes are removed. To help identify these barriers, we used a state and transition framework to compare topsoils of little-disturbed (reference) and variously degraded remnants of grassy Eucalyptus albens Benth. and E. melliodora Cunn. ex Schauer woodlands. Topsoils of degraded remnants showed a repeated pattern, with the most compacted, most acidic and most depleted topsoils occurring in remnants dominated by Aristida ramosa R.Br. or Austrodanthonia H.P.Linder and Austrostipa scabra (Lindl.) S.W.L.Jacobs & J.Everett; the least compacted and most nutrient rich topsoils in remnants dominated by annual exotics; and generally intermediate topsoils in remnants dominated by Bothriochloa macra (Steud.) S.T.Blake or Austrostipa bigeniculata (Hughes) S.W.L.Jacobs & J.Everett. Surprisingly, topsoils beneath trees in reference sites (supporting Poa sieberiana Spreng.) were similar to topsoils supporting annual exotics for most soil properties. Chemical properties of topsoils from open areas of reference sites [supporting Themeda australis (R.Br.) Stapf] were usually intermediate and similar to Bothriochloa macra and Austrostipa bigeniculata topsoils. The most striking exception to these trends was for soil nitrate, which was extremely low in all reference topsoils and showed a high correlation with annual exotic abundance. We discuss the potential for positive feedbacks between soil nitrogen cycling and understorey composition and the need for intervention to assist possible nitrate-dependent transitions between annual and perennial understorey states. Dominant grasses, trees and annual weed abundance may be useful indicators of soil conditions and could inform selection of target sites, species and techniques for restoration projects.

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