Mixture Of Granules Research Articles

PERFORMANCE OF FERTILIZER METERING MECHANISMS OF PLANTERS AS A FUNCTION OF LONGITUDINAL INCLINATION

ABSTRACT: Sowing occurs in agricultural areas with irregular relief, influencing the quality of seed and fertilizer distribution. The aim of this study was to analyze the performance of different fertilizer metering mechanisms of planters as a function of longitudinal inclination. The experimental design was a completely randomized design with five treatments and six replications. Treatments consisted of five longitudinal inclinations to the metering mechanism (−10, −5, 0, 5, and 10 degrees). The mass of fertilizer collected per minute was considered as a replication. We worked with two types of fertilizers: a mixture of granules and powder. Metering mechanisms used were a horizontal toothed rotor, helical without flow restrictor, helical with lateral overflow, and helical with longitudinal overflow. The longitudinal inclination of ±10° in relation to the leveling altered the metered amount of both fertilizers used in all metering mechanisms. The helical with lateral overflow was the metering mechanism that obtained the smallest amount variation of fertilizer distributed in the different longitudinal inclinations, followed by the helical with longitudinal overflow, horizontal toothed rotor, and helical without flow restrictor.

Prediction of Electrochemical Performance of Lower Temperature Operating Na-NiCl2 Battery

Sodium nickel chloride (Na-NiCl2) batteries are gaining growing attentions as a strong potential contender for advanced electric vehicle (EV) and stationary energy storage system (ESS) applications. The cathode compartment of a Na-NiCl2 battery features by a mixture of solid NaCl and Ni granules impregnated with a liquid NaAlCl4 catholyte. During charge-discharge cycles, complicated electrochemical reactions take place, including transportation of Na+ ions through NaAlCl4 catholyte, the dissolution/coarsening of NaCl particles, formation/decomposition of NiCl2 layers on the active Ni surface, and electron transport through the Ni granules. We are developing advanced Na-NiCl2 batteries that operate at relatively lower temperatures of below 200 °C to minimize its cell degradation typically observed at high operation temperature (over ~270 °C) and to enable application of simple and cheaper polymer seals for cell manufacturing. However, the diffusion and the ionic migration kinetics of active Na+ ions are restricted at the lower temperatures that may limit cell performance. In this presentation, we introduce a multi-physics continuum computational model to capture the electrochemical behaviors of planar lower temperature Na-NiCl2 batteries. The computational results will elucidate impacts of (i) cell operation temperatures, (ii) current densities, and (iii) cathode dimensions on the electrochemical performance of prototype planar Na-NiCl2 cells. The developed prediction model is expected to provide a useful guideline for the experimental fabrication of advanced Na-NiCl2 batteries with maximized cell performance at relatively lower temperatures.

Investigation of Dry Sliding Wear Properties of Aluminium Matrix Composite Prepared Through FDMAIC Process Using Reinforced Pattern

In the present research work an attempt has been made to investigate the dry sliding wear properties of Al-6063/Al2O3 based aluminium matrix composite (AMC) prepared through fused deposition modelling assisted investment casting route by using an alternative reinforced sacrificial pattern. Initially, a mixture of Al2O3 particles (120–150 μm), Al powder and nylon-6 granules was prepared with hand blending and was used for the development of alternative fused deposition modelling (FDM) feedstock filament. Afterwards, sacrificial patterns prepared on FDM with this alternative filament were used for investment casting (IC). Three controllable process parameters namely: volume of FDM pattern (VP), density of FDM system (DP) and number of IC layers (SL) were studied through Design of Experimental technique. Wear of aluminium matrix composites (AMCs) has been examined on pin-on-disc type tribo tester at 19.6 N load for 10 min. The results of the study indicated that VP, DP and SL have contributed about 3, 15 and 76% respectively, for wear resistance of AMCs.

Modified tribo-charging device for the electrostatic separation of plastics from granular industrial wastes

ABSTRACTTribo-electrostatic separation is the solution of choice for the selective sorting of various plastics contained in a granular mixture. This work is aimed at validating the efficiency of a modified compressed-air-operated tribo-charging device for the electrostatic separation of mixed granular plastics originating from industrial waste. The experiments are carried out with a mixture of mm-size orange and beige PVC granules, using a free-fall electrostatic separator. At optimum operating conditions, 93% of the orange PVC and 96% of the beige PVC were recovered at purities higher than, respectively, 99% and 95%. The numerical simulation of charged particles trajectories facilitates the interpretation of the experimental results and the analysis of the factors that affect the efficiency of the separation process: high-voltage level, configuration of the electrodes system, and position of the feeding unit.

Choice of Binder and Optimization of Slag-Forming Mixture Granulation Technology to Improve Granule Strength

A procedure is described for qualitative evaluation of the effect of binders on granulated slag-forming mixture (SFM) strength. A relationship is established for slip density and finished granulate bulk density on water content. Industrial tests are conducted for a new binder and a test batch of granulated SFM is prepared with a low proportion of dusty fraction for pouring steel in a CBCM at MMK.

EFFECT OF GRANULATION, MECHANICAL ACTIVATION, THERMOVACUUM TREATMENT AND AMBIENT GAS PRESSURE ON TI–0,5C SYSTEM SYNTHESIS REGULARITIES

This paper studies dependences of combustion velocities and changes in sample relative lengths from ambient pressure and thermovacuum degassing (TVD) time for the Ti + 0,5C mixture. It was shown that Ti + 0,5C mixture TVD significantly (doubly) increase combustion velocity as well as sample shrinkage. Sample shrinkage occurs under the influence of surface tension due the sufficient quantity of a liquid phase in combustion products that ensure their low viscosity. It was not possible before to obtain pressed samples from the mechanically activated (MA) Ti + C mixture because of their low strength, and therefore to investigate their combustion regularities. To solve this problem, the authors used preliminary granulation of the initial Ti + 0,5C mixture before MA. As a result, dependences of combustion velocity and post-combustion changes in sample lengths from MA time were obtained for the first time ever for the Ti + 0,5C preliminary granulated mixture. It was found that mechanical activation decreases mixture combustion velocity and significantly (triply) increases sample elongation after combustion. Combustion velocity after MA mixture TVD reaches combustion velocity of initial mixtures at the same TVD time. The samples of condensed reaction products from the MA mixture retained a slight elongation (within 8 %) after TVD. X-ray phase analysis revealed no reaction products formed during MA. Combustion products of all mixtures (initial, activated mixture and activated granules) contain the Ti2C phase and Ti traces. X-ray analysis of the initial and MA mixtures shows peaks intensity broadening and reduction of peak intensity to the background intensity ratio after MA thus indicating a higher defect rate in the crystal structure of the components of mixtures. This effect intensifies with an increase in activation time. The study results are interpreted based on the conduction – convection model of reaction wave propagation.

Experimental and numerical evaluation of two electrode systems for plate-type electrostatic separators

Plate-type electrostatic separators are commonly employed for the selective sorting of conductive and non-conductive granular materials. The separation generally takes place in the electric field generated between an elliptical electrode, which is connected to a high voltage supply, and a grounded S-shaped electrode. The aim of the present work is to evaluate the separation performances attainable with another electrode system, consisting of two metallic plates, a short one that is connected to the high-voltage and a long one that is grounded. The experiments are carried out with a mixture of mm-size granules of copper and PVC, originating from mechanically processed electric wire wastes. The results of the composite factorial experimental designs performed for each of the two electrode systems are quite similar. The numerical modelling and simulation of the electric field and of particle trajectories explain the experimental findings and support the practical recommendations regarding the industrial application of the two electrode systems.

Burning of the Ti + xC (1 > x > 0.5) powder and granulated mixtures

This paper describes the experiments on the burning of the Ti + 0.5C, Ti + 0.75C, and Ti + C powder and granulated mixtures. Despite the fact that there is no convective heat transfer and the contact area between the particles is small, the linear and mass burning rates of granulated compositions happened to be several times greater than in the case of powder mixtures of the same composition. The obtained experimental and computational values of the adiabatic combustion temperature were used to estimate the contribution of the radiant and conductive heat transfer in the combustion wave propagation along the granulated mixtures. The experiments with compacted samples showed that the high burning rate of the granulated mixtures is due to great velocity of the combustion wave propagation along the granule rather than the specific features of the original reagents.

Effect of charge mixture preparation technology on the physicochemical and optical properties of LiNbO3:Mg crystals

LiNbO3:MgO crystals, representing important materials for nonlinear optics, laser optics, integrated optics, and optical electronics owing to their high resistance with respect to optical damage, are studied. The crystals of LiNbO3:MgO were grown from a granulated charge mixture of lithium niobate synthesized using homogeneously doped Nb2O5:Mg precursors of different origin. The effect of organic substances used in the technology of lithium niobate charge mixture on the properties of LiNbO3:MgO single crystals is studied. It is found that the physicochemical and optical characteristics of LiNbO3:MgO crystals grown from charge mixtures synthesized from Nb2O5:Mg precursors obtained using organic solvents and without them differ to a considerable extent. It is suggested that the difference in the properties of LiNbO3:MgО crystals of different origin is caused by change in the structure of the ion complexes in the melt owing to the presence of traces of organic impurities. Change in the structure of ion complexes in the melt leads to change in crystallization mechanisms and, accordingly, in the chemical composition and the properties of LiNbO3:MgO crystals. Furthermore, it is shown that the use of homogeneous doping methods as opposed to the method of direct doping provides the distribution coefficient K eef > 1. That is, the method of homogeneous doping allows one to introduce a substantially greater concentration of an impurity element in the LiNbO3:MgO crystal compared with the direct method for doping the charge mixture at the same impurity concentration in the starting material.

Formation of a Segregated Electrically Conductive Network Structure in a Low-Melt-Viscosity Polymer for Highly Efficient Electromagnetic Interference Shielding

A segregated electrically conductive network structure has been well demonstrated to efficiently improve electrical and electromagnetic interference (EMI) shielding performance owing to the controllable assembling of conductive additives in polymer matrices; however, up to now, the polymer matrices are mainly limited to high-melt-viscosity polymers (e.g., ultrahigh molecular weight or cross-linked polymers). In the current work, we proposed a strategy to form a typical segregated structure in a low-melt-viscosity polymer, i.e., poly(lactic acid) (PLA), making use of the melting temperature difference of crystallites. Poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) were first melt mixed, then crystallized, herein the resultant blend consisted of homocrystallites (hc) and stereocomplex crystallites (sc), and, interestingly, spontaneously granulated into 100 μm particles during melt mixing and crystallizing. The mixture of PLA crystallite granules and carbon nanotubes (CNTs) was compression molded at a tem...

Comparative anatomy of calyx and foliar glands of Banisteriopsis C. B. Rob. (Malpighiaceae)

Banisteriopsis is considered one of the largest genera of Malpighiaceae with 58 species, of which 47 occur in Brazil. The typical calyx and leaf glands of Banisteriopsis are considered relevant to the adaptive success of Malpighiaceae. Comparative studies of anatomical and histochemical characteristics may reveal similarities and assist in the interpretation of the functions performed by such glands. The present study aimed to describe the anatomy of the calyx and leaf glands of 38 species ofBanisteriopsis that occur in Brazil, and to analyze these structures histochemically in B. campestris, B. laevifolia and B malifolia, using standard methods. Calyx glands differ from leaf glands by possessing an irregular surface that is covered by a thick cuticle that is released from the epidermis by the accumulation of secretion; the glands are similar in all the other anatomical characteristics. Both types of glands produce secretions composed of a mixture of protein granules, lipids and polysaccharides. These findings reinforce the hypothesis that foliar glands have given rise to calyx glands in response to interactions with pollinators.

Size-dependent calcium carbonate precipitation induced microbiologically in aerobic granules

Calcium and ash accumulation in aerobic granules treating organic wastewater was investigated systematically in this study. It was found that ash content of granular sludge reached 43% at stable state of reactor operation with calcium carbonate precipitation as the main cause. Since granular sludge in the reactor at the steady state was the mixture of granules with different sizes, granules in the reactor on operation days 90, 120 and 150, respectively, were sorted into 10 categories by size to study the inorganic substances. It was found that calcium was selectively enriched in granules and the precipitation of calcium carbonate was just dependent on granule size instead of operation duration at the steady state. More calcium carbonate was precipitated in bigger aerobic granules, but both calcium and ash contents reached stable values when granule size was bigger than 700μm. Analysis by X-ray diffractometer disclosed that aragonite was the only polymorph of calcium carbonate detected in aerobic granules with size bigger than 300μm. Scanning electron microscope revealed clearly for the first time that bundles of needle shaped aragonite was embedded in extracellular polymeric substances of aerobic granules. A mechanism on calcium carbonate precipitation was proposed to deepen the understanding of biomineralization.

Methods of adding micronutrients to a NPK formulation and maize development

ABSTRACTMicronutrients are essential for plant development; however, micronutrient content in soil often is not sufficient. This study compared availability of boron (B), copper (Cu), manganese (Mn), and zinc (Zn) in the soil and their effect in developing maize plants, supplied from a physical mixture of nitrogen, phosphorus, and potassium (NPK) granules and micronutrients or from a granulated mixture of NPK coated with these micronutrients. The experiment was conducted in a greenhouse, with a Rhodic Acrustox soil and the formulation 4-30-10 [nitrogen-phosphorus pentoxide-potassium oxide (N-P2O5-K2O)] with 0.1% B, 0.2% Cu, 0.2% Mn, and 0.3% Zn. A randomized block design with four replicates was used and the NPK formula doses used were 0, 150, 300, 600, 1200, and 2400 kg/ha. Coated NPK increased Zn levels in soil in 0.5 mg/dm3 in relation to its initial content, also causing an increase in plant dry matter. Compared with mixture, this increase was more than three times greater. Cu and Zn accumulation and Zn absorption were greater when their supply was made via coated granules. The larger dose of B via coated granules resulted in a greater B accumulation in comparison to the mixture. No differences were observed for the other variables when comparing both sources. Coating NPK granules with micronutrients was better than the mixture when comparing B, Cu, and Zn concentrations in the soil. Dry matter production of maize shoots and the accumulation of B, Mn, Cu, and Zn in it was greater when the fertilizer was coated with micronutrients.

Electrostatic separator for micronized mixtures of metals and plastics originating from waste electric and electronic equipment

In spite of their extensive use for processing mixtures of granules exceeding 1 mm in size, very few industrial electrostatic separators are capable of handling micronized metals and plastics originating from waste electric and electronic equipment. The aim of the present work is to validate the possibility of using a novel belt-type electrostatic separator for the selective sorting of such particulate mixtures, the dimensions of which are in the order of 0.1 mm. In this type of separator, the metal particles get charged by electrostatic induction in contact with the grounded metal belt electrode, while the plastics remain uncharged in the electric field and are collected separately. The experiments are performed with 2-g samples of a mixture composed in equal proportions (50% - 50%) of Aluminium and Acrylonitrile Butadiene Styrene (ABS) particles of average diameter ranging between 125 μm and 250 μm. They enabled the evaluation of the effects and the interaction of two control variables of the process: the angle of inclination of the roll-type electrode and the high voltage applied to it.

Preservazione dell’alveolo e della cresta mediante nanoidrossiapatite in miscela con acido polilattico e poliglicolico: valutazioni istologiche

ObjectivesThe aim of this study was to histologically evaluate the results obtained with alveolar bone volume maintenance techniques using a bio-based material made of nano-hydroxyapatite conveyed by polylactic and polyglycolic acid. Materials and methodsTwo clinical cases were presented, in which the patient was subjected to tooth extraction and alveolus filling with a mixture of nano-hydroxyapatite granules (70 nm diameter) and of polylactic and polyglycolic acid copolymers (Fisiograft® nano-H.A.reinforced, Ghimas SpA, Casalecchio di Reno, Bologna, Italy). About 6 months later, at the time of implant surgery, bone samples were harvested for histological examination. ResultsAt six months from surgery, the bio-material placed in the alveolus appeared homogeneous and integrated into the new bone formation. Histomorphometric quality assessment allowed to quantify the percentage of newly formed bone (70.82%), of residual nano- hydroxyapatite (3.80%) and of bone marrow spaces (25.38%) in the regenerated sites. ConclusionsThe use of nano-hydroxyapatite in socket and ridge preservation techniques seems to allow a larger newly formed bone quantity as compared with slow resorption materials.

Styles of early diagenesis and the preservation potential of onshore tsunami deposits—A re-survey of Isla Mocha, Central Chile, 2 years after the February 27, 2010, Maule tsunami

The style of early diagenesis and preservation of onshore tsunami deposits are poorly constrained. Only tsunami surveys and subsequent re-surveys can fill this information gap. Here we present the results of a first re-survey in 2012 on Isla Mocha following the original survey in 2010 in the wake of the February 27, 2010, Maule earthquake and tsunami in central Chile. As a result of this tsunami, a large number of boulders consisting of clay-rich fine sandstones representing the Miocene age bedrock of the island had been transferred from the tidal to shallow subtidal zone onto the coastal plain. Coarse clastic sediment mixtures of pebbles, granules, and sand entrained at coastal plain terraces and transported up to the maximum runup position c. 600m from the coast by the inflow had been left behind as extensive backflow blankets on the lower coastal plain.In 2012, vegetation had covered the 2010 tsunami deposits. Sediment beyond 200m from the coast had been removed by a combination of surface processes and grazing cattle. Grain-size distributions of the preserved sediment show an increase of the sand fraction at the expense of the coarser grain sizes. Boulders show patterns resembling mud cracks on the surface and evidence of disintegration into smaller fragments and sand. Veneers of dried algae documenting the derivation of the boulders from the tidal zones had flaked off partly or completely from most rock surfaces. At the northern, wind-facing coast of the island, a c. 130m long and 1.2m high beach ridge had accumulated, most likely from reworked tsunami sediment.Boulders deposited by tsunamis are commonly assigned a high preservation potential. We demonstrate for the first time that such boulders may in fact disintegrate rapidly and disappear from the record over short geological time scales, given a lithology susceptible to weathering.The degree of modification to the lsla Mocha tsunami boulders and deposits strongly questions the applicability of inverse models using paleotsunami deposit thickness and grain-size distributions to infer parameters and magnitudes of the causative tsunamis. Inverse models would consequently underestimate tsunami flow parameters and may result in the inference of erroneous transport modes and event magnitudes. Our study gives strong evidence in support of re-survey studies following the deposition of tsunami sediments by tracing and quantifying the changes affecting them.

Experimental and Numerical Modeling of a New Tribo-Electrostatic Separation Process for Granular Plastics Mixtures

The paper aims at optimizing the operation of a free-fall electrostatic separator equipped with a novel tribo-charging device for the processing of granular plastic mixtures. Experiments were performed with a mixture of polycarbonate and polyamide granules (cylinders of 1.5 mm in diameter and 3 mm in length). The samples of granules to be charged were introduced in the gap between the two co-axial cylinders of the tribo-charging device, and were put into turbulent motion for 30 s by two oppositely oriented air jets (pressure: 2 bar). Then, the charged particles were left to fall freely between the vertical plate electrodes of an electrostatic separator. A composite experimental design enabled the modeling and optimization of the tribo-electrostatic separation process as a function of the following control factors: applied high voltage, inter-electrode distance, and the inclination angle of the feeding device. Under optimal conditions, the purity obtained is close to 99%. A numerical model of particle trajectories confirms the conclusions of the experimental study. The simulations point out the effect of each control variable on the outcome of the separation process.

Study on Durability of Granulated Crumb Rubber Asphalt Pavement Based on TPS High-Viscosity Asphalt

In order to improve the durability of granulated crumb rubber asphalt pavement, different amount of TPS modifier are added into granulated crumb rubber asphalt mixture to do tests of water-boiling, water immersion, immersing Marshall, cantabro immersion and some other indoor experiments. Through comparing with base asphalt and SBS modified asphalt, we found that the adhesion ability of asphalt and mineral aggregate and crumb rubber were granulated after adding TPS modifier. The water stability of granulated crumb rubber asphalt mixture is improved. The durability of granulated crumb rubber asphalt mixture has also been improved dramatically. In additions, the optimum mixing volume of TPS for granulated crumb rubber asphalt mixture is 12%; the mixing temperature of asphalt mixture is 185°C.

Research on Ice-Broken Effect of Granulated Rubber Asphalt Mixture High-Elastic Deck Pavement on Bridge

They are researched about the influence of ice-broken performance of granulated crumb rubber amount of admixture, thickness of pavement layer, thickness of ice layer and temperature to granulated crumb rubber asphalt mixture by the method of laboratory simulation test. From the research it is indicated that the closer the granulated crumb rubber approach to upper surface of mixture, the larger the amount of admixture is, the more thickness the surface of granulated crumb rubber asphalt mixture is, the better effect of wiping ice off will be. With the reduction of temperature and increase of ice layer thickness, the effect of wiping ice off through granulated crumb rubber asphalt mixture will weaken gradually.

Influence of humidity on the combustion of powdered and granulated Ti + 0.5C mixtures

The combustion of both powdered and granulated Ti + 0.5 C mixtures at various moisture contents in an initial mix as in argon flow (coflow filtration) and without gas flow has been ascertained. The combustion velocity of ‘wet’ Ti + 0.5 C powder in an argon flow under 1 atm pressure difference decreases almost by one half in comparison to ‘dry’ mixture, while for granulated mixtures the moisture influence on combustion velocity and phase structure of the final products is insignificant.