Journal articles on the topic 'Particle feeding techniques'
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Riisgård, Hans Ulrik, and Poul S. Larsen. "A comment on experimental techniques for studying particle capture in filter-feeding bivalves." Limnology and Oceanography 45, no. 5 (July 2000): 1192–95. http://dx.doi.org/10.4319/lo.2000.45.5.1192.
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Wang-Li, Lingjuan, Zihan Cao, Michael Buser, Derek Whitelock, Calvin B. Parnell, and Yuanhui Zhang. "Techniques for measuring particle size distribution of particulate matter emitted from animal feeding operations." Atmospheric Environment 66 (February 2013): 25–32. http://dx.doi.org/10.1016/j.atmosenv.2012.08.051.
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Klump, J. Val, John R. Krezoski, Michael E. Smith, and Jerry L. Kaster. "Dual Tracer Studies of the Assimilation of an Organic Contaminant from Sediments by Deposit Feeding Oligochaetes." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 9 (September 1, 1987): 1574–83. http://dx.doi.org/10.1139/f87-190.
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The assimilation of [14C]2,4,5,2′,4′,5′-hexachlorobiphenyl (HCBP) from Lake Michigan sediments by oligochaete worms was determined in laboratory microcosms using dual tracer techniques. Particle size selective feeding by oligochaetes makes single tracer calculations of assimilation from bulk feces subject to errors resulting from the changing distribution coefficients of adsorbed constituents as a function of particle size. 51Cr3+ adsorbed to sediments passes through the guts of worms without being assimilated and serves as a conservative tracer of ingestion. Assimilation efficiencies for HCBP decreased from 36 to 15% over the initial 10 d of active feeding and was inversely related to average defecation rate which increased from 0.05 to 0.25 mg sediment∙mg worm−1∙h−1 over the same period. In combination with measured defecation rates, assimilation efficiencies were used to estimate HCBP uptake rates of 3.9–8.1 pmol∙mg worm−1∙h−1. Assimilation efficiencies appear to be dependent upon gut clearing times which are a function of both gut volume and feeding rate and which are estimated to vary from <1 to >5 h.
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Janssen, Pauline H. M., Sébastien Depaifve, Aurélien Neveu, Filip Francqui, and Bastiaan H. J. Dickhoff. "Impact of Powder Properties on the Rheological Behavior of Excipients." Pharmaceutics 13, no. 8 (August 4, 2021): 1198. http://dx.doi.org/10.3390/pharmaceutics13081198.
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With the emergence of quality by design in the pharmaceutical industry, it becomes imperative to gain a deeper mechanistic understanding of factors impacting the flow of a formulation into tableting dies. Many flow characterization techniques are present, but so far only a few have shown to mimic the die filling process successfully. One of the challenges in mimicking the die filling process is the impact of rheological powder behavior as a result of differences in flow field in the feeding frame. In the current study, the rheological behavior was investigated for a wide range of excipients with a wide range of material properties. A new parameter for rheological behavior was introduced, which is a measure for the change in dynamic cohesive index upon changes in flow field. Particle size distribution was identified as a main contributing factor to the rheological behavior of powders. The presence of fines between larger particles turned out to reduce the rheological index, which the authors explain by improved particle separation at more dynamic flow fields. This study also revealed that obtained insights on rheological behavior can be used to optimize agitator settings in a tableting machine.
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Beninger, Peter G., and Marcel Le Pennec. "Histochemistry of the Bucco-Oesophageal Glands of Mytilus Edulis: The Importance of Mucus in Ingestion." Journal of the Marine Biological Association of the United Kingdom 73, no. 1 (February 1993): 237–40. http://dx.doi.org/10.1017/s002531540003277x.
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Histochemical techniques were used to investigate the possible role of the buccooesophageal glands in the blue mussel, Mytilus edulis L. (Mollusca: Bivalvia). No activity was observed for any of the eight major digestive enzymes tested; however, the glands contained large amounts of both neutral and acid mucopolysaccharides. These results confirm the importance of mucus in the ingestive process in M. edulis, and do not support the hypothesis of ingestion of particles suspended in water alone.Until recently it was thought that the Bivalvia were the only class of molluscs in which some type of secretory gland of extracellular digestive function in the bucco-oesophageal region was totally absent (Table 1). However, in a study of the mode of particle ingestion in five species of suspension-feeding bivalves, an extensive glandular complex was reported in the bucco-oesophageal region of Mytilus edulis L. only (Beninger et al., 1991). Although these glands were observed to liberate secretions into the oesophageal lumen, it was not known whether they performed any digestive function.
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Radiša, Radomir, Nedeljko Dučić, Srećko Manasijević, Nemanja Marković, and Žarko Ćojbašić. "CASTING IMPROVEMENT BASED ON METAHEURISTIC OPTIMIZATION AND NUMERICAL SIMULATION." Facta Universitatis, Series: Mechanical Engineering 15, no. 3 (December 9, 2017): 397. http://dx.doi.org/10.22190/fume170505022r.
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This paper presents the use of metaheuristic optimization techniques to support the improvement of casting process. Genetic algorithm (GA), Ant Colony Optimization (ACO), Simulated annealing (SA) and Particle Swarm Optimization (PSO) have been considered as optimization tools to define the geometry of the casting part’s feeder. The proposed methodology has been demonstrated in the design of the feeder for casting Pelton turbine bucket. The results of the optimization are dimensional characteristics of the feeder, and the best result from all the implemented optimization processes has been adopted. Numerical simulation has been used to verify the validity of the presented design methodology and the feeding system optimization in the casting system of the Pelton turbine bucket.
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Siljanovska Petreska, Gordana, Christof van Sluijs, Clemens Auschra, and Maria Paulis. "Design of Waterborne Asymmetric Block Copolymers as Thermoresponsive Materials." Polymers 12, no. 6 (May 30, 2020): 1253. http://dx.doi.org/10.3390/polym12061253.
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AB diblock waterborne copolymers made of styrene (St) and 2-ethylhexyl acrylate (2EHA) were synthesized by means of two-step reversible addition fragmentation chain transfer (RAFT) (mini)emulsion polymerization. Monofunctional asymmetric RAFT agent was used to initiate the polymerization. The hard polystyrene “A” block was synthesized via miniemulsion polymerization followed by 2EHA pre-emulsion feeding to form the soft “B” block. Polymerization kinetics and the evolution of the molecular weight distribution were followed during synthesis of both initial and final block copolymers. DSC measurements of the block copolymers revealed the existence of two glass transition temperatures (Tgs) and thus the occurrence of two-phase systems. Microscopic techniques (atomic force microscopy (AFM) and transmission electron microscopy (TEM)) were used to study the phase separation within the particles in the latex form, after film formation at room temperature cast directly from the latex and after different post-treatments well above the Tg of the hard-polystyrene domains, when complete particle coalescence had occurred. The morphological differences observed after different annealing temperatures were correlated with the mechanical properties analyzed by DMTA measurements. Finally, the differences found in the mechanical properties of the block copolymers annealed at different temperatures were correlated to their heat seal application results.
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Pavageau, M., E. M. Nieto, and C. Rey. "Odour and VOC confining in large enclosures using air curtains." Water Science and Technology 44, no. 9 (November 1, 2001): 165–71. http://dx.doi.org/10.2166/wst.2001.0532.
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Experiments were conducted on a two stream air-curtain prototype designed for VOC and odour confinement in a truck unloading area. The emphasis was placed on the air supply device. Measurements using tracer gas techniques were performed to assess the effectiveness of the system in terms of air tightness. Leakage flow rate was estimated for various feeding arrangements. Flow visualisations and particle image velocimetry measurements were carried out for a better understanding of the flow dynamics. Evidence was given of the improvements brought by the herein referred to, “double flux” configuration in comparison to traditional designs. After a brief description of the experimental facility and the basic principle underlying the approach developed, the main results are reported and discussed and recommendations are drawn. Considerations about where the effort will be directed in future works are provided.
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Zhu, D., N. M. Linke, M. Benedetti, K. A. Landsman, N. H. Nguyen, C. H. Alderete, A. Perdomo-Ortiz, et al. "Training of quantum circuits on a hybrid quantum computer." Science Advances 5, no. 10 (October 2019): eaaw9918. http://dx.doi.org/10.1126/sciadv.aaw9918.
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Generative modeling is a flavor of machine learning with applications ranging from computer vision to chemical design. It is expected to be one of the techniques most suited to take advantage of the additional resources provided by near-term quantum computers. Here, we implement a data-driven quantum circuit training algorithm on the canonical Bars-and-Stripes dataset using a quantum-classical hybrid machine. The training proceeds by running parameterized circuits on a trapped ion quantum computer and feeding the results to a classical optimizer. We apply two separate strategies, Particle Swarm and Bayesian optimization to this task. We show that the convergence of the quantum circuit to the target distribution depends critically on both the quantum hardware and classical optimization strategy. Our study represents the first successful training of a high-dimensional universal quantum circuit and highlights the promise and challenges associated with hybrid learning schemes.
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Kavinkumar Sakthivel, Krishnanand Anilkumar, Jawahar Natarajan, and Senthil Venkatachalam. "A promising method to enhance the solubility of poorly water soluble drug by using hot-melt extrusion technique." International Journal of Research in Pharmaceutical Sciences 11, no. 3 (July 18, 2020): 3657–66. http://dx.doi.org/10.26452/ijrps.v11i3.2526.
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More than 40% of new chemicals are of poor solubility, it causes poor bioavailability. Several techniques are available to increase the solubility of drugs, such as converting the drug into salt form, complexion, co-solvency, particle size reduction, nano-suspension, cryogenic technique, modification of crystal habit etc. Hot melt extrusion has increased wide acknowledgment in the recent past. Over the past recent three decades modern flexibility has permitted hot melt extrusion (HME) is to increase wide acknowledgment and has just settled its place in the wide range of assembling activities and pharmaceutical research advancements. HME has just been exhibited as a vigorous, novel system to cause strong scatterings so as to give time controlled, changed, broadened, and focused on medicate conveyance bringing about improved bioavailability just as taste covering of bitter Active Pharmaceutical Ingredients (APIs). Hot melt extrusion is one of the efficient technique for improving the solubility of hydrophobic drugs by forming solid dispersion. It is a solventfree process and time taken for the production is less. The process involved in this technique include, weighing/feeding, Melting, Mixing, Venting, Extrusion, Cooling, Pelletizing. Solubility of many drugs have improved by utilizing hot melt-extrusion technology. In this review, a detailed overview about Solubility enhancement of drugs by hot-melt extrusion and its applications are discussed. This review summarizes the importance and uses of solid dispersion technique for improving the solubility of poorly soluble drugs
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Mahmoud, M. G., A. M. Samuel, H. W. Doty, S. Valtierra, and F. H. Samuel. "Effect of Rare Earth Metals, Sr, and Ti Addition on the Microstructural Characterization of A413.1 Alloy." Advances in Materials Science and Engineering 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/4712946.
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The present work was performed on A413.1 alloy containing 0.2–1.5 wt% rare earth metals (lanthanum or cerium), 0.05–0.15% Ti, and 0–0.02 wt% Sr. These elements were either added individually or combined. Thermal analysis, image analysis, and electron probe microanalysis were the main techniques employed in the present study. The results show that the use of the depression in the eutectic temperature as a function of alloy modification cannot be applied in the case when the alloy is treated with rare earth metals. Increasing the concentration of RE increases the solidification zone especially in Sr-modified alloys leading to poor feeding ability. This observation is more prominent in the case of Ce addition. Depending upon the amount of added Ti, two RE based intermetallics can be formed: (i) a white phase, mainly platelet-like (approximately 2.5 μm thick), that is rich in RE, Si, Cu, and Al and (ii) a second phase made up of mainly grey sludge particles (star-like) branching in different directions. The grey phase is rich in Ti with some RE (almost 20% of that in the white phase) with traces of Si and Cu. There is a strong interaction between RE and Sr leading to a reduction in the efficiency of Sr as a eutectic Si modifier causing particle demodification.
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Zaefarian, Faegheh, Mohammad Abdollahi, Aaron Cowieson, and Velmurugu Ravindran. "Avian Liver: The Forgotten Organ." Animals 9, no. 2 (February 15, 2019): 63. http://dx.doi.org/10.3390/ani9020063.
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Despite having huge responsibilities in avian species, published reports on the influence of dietary factors and other possible constraints on the size, development and function of liver are limited. Consideration of the factors that could influence and alter liver function is therefore of critical relevance. In the current review, aspects of liver structure and function, and the influence of feed restriction, anti-nutritional factors, structural components and feed additives on liver are discussed. Effects of feed technology techniques such as thermal treatment and pelleting, feed particle size and whole grain feeding on the liver are also reviewed. A discussion of lipogenesis and lipid storage in poultry is presented to provide a better understanding and to differentiate the normal pathways of lipid metabolism from abnormal (i.e., disordered) pathways. The liver is the main site of fat synthesis in poultry, but under certain conditions, excessive fat can accumulate in the liver and cause problems. Factors contributing to the fatty liver syndrome are also examined.
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Díaz-Royón, F., J. M. Arroyo, M. D. Sánchez-Yélamo, and J. González. "Sunflower meal and spring pea ruminal degradation protection using malic acid or orthophosphoric acid-heat treatments." Animal Production Science 56, no. 12 (2016): 2029. http://dx.doi.org/10.1071/an14669.
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The effects of solutions of malic or orthophosphoric acids (0.752 Eqg/kg of feed) and heat to protect proteins of sunflower meal (SFM) and spring pea (SP) against ruminal degradation were studied using particle transit, 15N infusion, in situ and electrophoretic techniques. Three wethers fitted with rumen and duodenum cannulae were successively fed three isoproteic diets including SFM and SP, untreated or treated with malic or orthophosphoric acids. Incubations of tested meals were only performed while feeding the respective diet. Estimates of the ruminally undegraded fraction (RU) and its intestinal digestibility of dry matter, organic matter (only for RU), crude protein and starch (only in SP) were obtained considering ruminal microbial contamination and particle comminution and outflow rates. When corrected for microbial contamination, estimates of RU and intestinal digestibility decreased in all tested fractions for both feeds. All RU estimates increased with the protective treatments, whereas intestinal digestibility-dry matter also increased in SFM. Low intestinal digestibility-crude protein values suggested the presence of antitrypsin factors in SP. Protective treatments of both feeds led to consistent increases in the intestinal digested fraction of dry matter and crude protein, being only numerically different for SP-starch (60.5% as average). However, treatments also reduced the organic matter fermentation, which may decrease ruminal microbial protein synthesis. Electrophoretic studies showed albumin disappearance in both SFM and SP, whereas changes in other RU proteins were more pronounced in SP than SFM.
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Siljanovska Petreska, Gordana, Arantxa Arbe, Clemens Auschra, and Maria Paulis. "Mechanical and Morphological Properties of Waterborne ABA Hard-Soft-Hard Block Copolymers Synthesized by Means of RAFT Miniemulsion Polymerization." Polymers 11, no. 8 (July 30, 2019): 1259. http://dx.doi.org/10.3390/polym11081259.
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High molecular weight waterborne ABA block copolymers of styrene (St) and 2-ethylhexyl acrylate (2EHA) containing hard and soft domains were synthesized by means of RAFT (mini)emulsion polymerization using a bifunctional symmetric S,S-dibenzyl trithiocarbonate (DBTTC) RAFT agent. Miniemulsion polymerization was initially used for the synthesis of the A-block, which forms hard domains, followed by 2EHA pre-emulsion feeding to build the B-block soft domains. Polymerization kinetics and the evolution of the Molecular Weight Distribution (MWD) were followed during the synthesis of different ABA block copolymers. The thermal properties of the final symmetric block copolymers were studied on dried films by means of DSC. It was found that the block copolymers have two glass transitions, which indicates the presence of a two-phase system. Phase separation was investigated by means of microscopic techniques (AFM and TEM) and SAXS, both of the particles in the latex form, as well as after film formation at room temperature and after different post-treatments. Films were annealed at temperatures well above the glass transition temperature (Tg) of the hard phase to study the bulk morphology of the films after complete particle coalescence. Moreover, for comparison purposes, the films were re-dissolved in THF, and films were again cast directly from the homogeneous THF solutions. As THF is a good solvent for both blocks, such films serve as a reference for the equilibrium morphology. Finally, DMTA studies of the films annealed at different temperatures were performed to correlate the morphology changes with the mechanical properties of the block copolymers.
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Rulyov, N. N., L. O. Filippov, D. Y. Sadovskyi, V. V. Lukianova, and I. V. Filippova. "Reverse Column Flotation of Ultrafine Magnetite Mixture with Fine Glass Beads Enhanced by Fine Bubbles." Minerals 12, no. 5 (May 5, 2022): 584. http://dx.doi.org/10.3390/min12050584.
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Magnetite ores are among the most important sources of iron, which is in high demand in the global economy. Metallurgical properties of the magnetite concentrate significantly depend on impurities of silicon- and aluminum-bearing minerals. These impurities have to be separated from ore by magnetic separation and flotation techniques. Reverse column flotation is one of the methods applied for reducing the content of impurities in magnetite concentrate. This method allows recovering impurities from ore in the froth product (flotation tailings). However, the efficiency of this method significantly decreases with the decrease in particle size. As previously demonstrated, the effectiveness of fine particle column flotation can be increased if, before feeding the pulp into a column, fine bubbles are introduced into the pulp and the pulp is then passed through a tubular reactor. The major purpose of this study was to define the effectiveness of the reverse column flotation performance of ultrafine magnetite from the mixture with fine glass beads (ballotini) when, before the pulp is fed into the flotation column, it is mixed with fine air-in-water dispersion, and the mixture is then passed through a tubular flotation reactor (TFR). The obtained experimental findings allowed the definition of the optimal conditions of the mixture treatment in TFR that ensured high concentrate grade and iron recovery for the initial iron content in the mixture of 63.76%. These conditions were defined as follows: treatment time of the mixture in the TFR—7.5 s; average flow shear rate inside the TFR—1000 s−1; volume dosage of fine bubbles per solid mass unit—0.032 or 0.21 mL/g. At the fine bubble dosage of 0.032 mL/g, the iron recovery and the concentrate grade were, respectively, 88.1% and 68.3% Fe, and at the dosage of 0.21 mL/g, the iron recovery reached 89.4% for the concentrate grade of 68.7% Fe.
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Miller, Neil R., Lee H. Monsein, Gerard M. Debrun, Rafael J. Tamargo, and Haring J. W. Nauta. "Treatment of carotid-cavernous sinus fistulas using a superior ophthalmic vein approach." Journal of Neurosurgery 83, no. 5 (November 1995): 838–42. http://dx.doi.org/10.3171/jns.1995.83.5.0838.
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✓ The authors describe the method and results of treatment of 12 consecutive patients with carotid-cavernous sinus fistulas (CCFs). Treatment was by embolization via a transvenous approach through the superior ophthalmic vein (SOV). The CCFs (two direct and 10 dural) had previously been treated unsuccessfully or, for mechanical reasons, could not be treated by the standard techniques of endoarterial balloon occlusion, particle or glue embolization of feeding vessels from one or both external carotid arteries, or transvenous occlusion of the fistula via the ipsilateral inferior petrosal sinus. All 12 patients were successfully treated either by advancement of a detachable balloon catheter through the ipsilateral SOV into the cavernous sinus with subsequent inflation and detachment of the balloon (11 patients) or by introduction of multiple thrombogenic coils into the fistula via the ipsilateral SOV (one patient). All patients had complete resolution of symptoms and signs after successful occlusion of the CCF. There were no intraoperative complications; however, one patient required postoperative embolization of a residual posteriorly draining fistula via the ipsilateral external carotid artery, and another developed a persistent abducens nerve paresis that eventually required surgical correction. Ten (83.3%) of the 12 patients underwent cerebral angiography 3 to 6 months after surgery, and none showed evidence of a recurrent fistula. Similarly, none of the 12 patients developed recurrent symptoms and signs suggesting recurrence of the fistula during a follow-up period that ranged from 6 months to 10 years (mean 64 months). It is concluded that the transvenous approach to the cavernous sinus through the SOV is a safe and effective treatment of both direct and dural CCFs that are not amenable to transarterial or other transvenous approaches.
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Yu, J. K., Q. Yan, and Pin Yang Fang. "Solidification of Aluminum Infiltrated Composites." Materials Science Forum 475-479 (January 2005): 901–4. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.901.
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The solidification and defects of Al/SiC and Al/C composites were investigated by directional solidification techniques. The solidification and defects of Al/SiC composites are greatly influenced by temperature gradients, solidification rates, the size of SiC particles and the chemical composition of magnesium, but slightly by the volume fraction of SiC particles and the chemical composition of silicon. The solidification shrinkage feeding of Al/C composites is greatly improved by hybridizing carbon fiber bundles with 3 vol% of SiC particles. A model of the solidification feeding was proposed and the solidification feeding distance was derived according to the preform geometry.
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Angeles-Martinez, Liliana, and Vassily Hatzimanikatis. "Spatio-temporal modeling of the crowding conditions and metabolic variability in microbial communities." PLOS Computational Biology 17, no. 7 (July 22, 2021): e1009140. http://dx.doi.org/10.1371/journal.pcbi.1009140.
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The metabolic capabilities of the species and the local environment shape the microbial interactions in a community either through the exchange of metabolic products or the competition for the resources. Cells are often arranged in close proximity to each other, creating a crowded environment that unevenly reduce the diffusion of nutrients. Herein, we investigated how the crowding conditions and metabolic variability among cells shape the dynamics of microbial communities. For this, we developed CROMICS, a spatio-temporal framework that combines techniques such as individual-based modeling, scaled particle theory, and thermodynamic flux analysis to explicitly incorporate the cell metabolism and the impact of the presence of macromolecular components on the nutrients diffusion. This framework was used to study two archetypical microbial communities (i) Escherichia coli and Salmonella enterica that cooperate with each other by exchanging metabolites, and (ii) two E. coli with different production level of extracellular polymeric substances (EPS) that compete for the same nutrients. In the mutualistic community, our results demonstrate that crowding enhanced the fitness of cooperative mutants by reducing the leakage of metabolites from the region where they are produced, avoiding the resource competition with non-cooperative cells. Moreover, we also show that E. coli EPS-secreting mutants won the competition against the non-secreting cells by creating less dense structures (i.e. increasing the spacing among the cells) that allow mutants to expand and reach regions closer to the nutrient supply point. A modest enhancement of the relative fitness of EPS-secreting cells over the non-secreting ones were found when the crowding effect was taken into account in the simulations. The emergence of cell-cell interactions and the intracellular conflicts arising from the trade-off between growth and the secretion of metabolites or EPS could provide a local competitive advantage to one species, either by supplying more cross-feeding metabolites or by creating a less dense neighborhood.
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Kukkonen, U., and P. Huhtanen. "Rate of passage calculations based on marker or rumen evacuation technique." Proceedings of the British Society of Animal Production (1972) 1991 (March 1991): 109. http://dx.doi.org/10.1017/s0308229600020596.
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The clearance rate of digesta from the reticulo-rumen may limit feed intake and thus production in ruminants. The longer the retention time in the rumen the better the cell wall carbohydrates are digested. However, a fast rate of passage of indigestible feed particles to the lower digestive tract is essential for maximal feed intake. The feeding level, type of diet and the physical characteristics of the feed particles affect the rate of passage from the rumen. The rate of passage has mostly been determined by external marker techniques. Because of physico-chemical characteristics these markers do not always accurately represent the behaviour of feed.particles. An alternative method, the rumen evacuation technique, may describe better the kinetic characteristics of cell walls. In this study marker and rumen evacuation techniques were compared in the determination of the passage rate and retention times.
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Asokan, Manivannan, Sasikumar Rathinasabapathy, Shaik Dawood Abdul Khadar, and Mohammed Sadique Khan. "Novel Combined Feeding Approach to Produce Quality Al6061 Composites for Heat Sinks." High Temperature Materials and Processes 38, no. 2019 (February 25, 2019): 647–50. http://dx.doi.org/10.1515/htmp-2019-0009.
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AbstractThis elementary work aims to address agglomeration and non-uniform dispersion of reinforcement particles in stir casting using Al6061 alloy (AA 6061) as a matrix and Aluminium oxide (Al2O3) as reinforcement particles. A novel combined feeding method of Encapsulate feeding technique & Two Step Stir Casting was developed & attempted to produce good quality composites by varying weight fractions of Aluminium Oxide (0 to 5 wt.%). The wetting agent Mg (2 wt.%) added in all castings to ensure better binding between ceramics and matrix. The SEM photomicrograph ensures homogenous dispersion of reinforcement particles by combined feeding method. The thermal properties of produced good quality composites are enhanced with increase in Aluminium Oxide (Al2O3) from 0 to 5 wt.%.
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Gaurav, Sharma, and Tewari P.C. "Performability Analysis for Feeding Unit of a Sugar Plant using Particle Swarm Optimization Technique." International Journal of Performability Engineering 15, no. 11 (2019): 2835. http://dx.doi.org/10.23940/ijpe.19.11.p1.28352842.
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Oh, Se Young, and Tae Jin Kang. "Preparation and characterization of electro-responsive core-sheath fiber mats for smart materials." Textile Research Journal 87, no. 9 (November 13, 2016): 1142–51. http://dx.doi.org/10.1177/0040517516646053.
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Multi-walled carbon nanotubes coated with inorganic materials were spun with polyethylene terephthalate with a core-sheath structure using co-axial electrospinning technique. The effect of electrorheological (ER) particle content on the morphology, rheological and mechanical properties has been studied. It has been shown that ER particles were homogeneously distributed throughout the core part of the fibers with the core-sheath structure. It has been uniformly fabricated by controlling the viscosity and conductivity of ER fluids as well as the applied voltage, feeding rate of the electrospinning systems. The tensile test results with fiber mats showed that the modulus and tensile strength of the fiber mats is enhanced with lower breaking elongation because of the instant increase of viscosity and yield stress of ER fluid in the core part under the external applied electric field. Fiber mats with ER fluids in the core of the fiber may find potential applications in the area of adaptive textile structures.
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Kyle, D. J., F. D. DeB Hovell, and J. Bajracharya. "The effect of fineness of grinding of a sample on the loss of material from nylon bags incubated in the rumen of sheep." Proceedings of the British Society of Animal Production (1972) 1987 (March 1987): 123. http://dx.doi.org/10.1017/s0308229600035571.
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The measurement of the degradability of a roughage by means of the nylon bag technique usually requires the preparation of the sample by grinding with a laboratory hammer mill. There is a wide range of screen sizes available which produce samples which range from a fine flour to coarser materials containing particles several millimeters in length. The objective of this experiment was to examine the effect of fineness of grinding on the degradation of roughages as measured by the nylon bag technique.Samples of hay and barley straw were ground through a 1 mm screen (fine) or through a bar screen with 3-5 by 33 mm slots (coarse). Two grammes contained in nylon bags were incubated in the rumen of each of four sheep fed on a good quality roughage, giving four observations per sample. All bags were introduced into the rumen at the same time relative to feeding. Zero-time losses were determined by washing bags without incubation. Water soluble material by filtration through a Whatman No. 1 filter paper. The particle size distribution of the hay used in Expt 1 is shown by Fig 1.
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Kotov, B. I., V. O. Hryshchenko, S. M. Hrushetskiy, and A. V. Rud. "Justification of the layout and operating mode of a vortex-dedusting device as part of heat recovery units in agro-industrial facilities." Mehanization and electrification of agricultural, no. 13(112) (2021): 116–25. http://dx.doi.org/10.37204/0131-2189-2021-13-12.
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Annotation Purpose. Determination of the efficiency of functioning of the centrifugal dust collector of exhaust ventilation air when supplied to the heat exchanger, and the parameters of the dedusting device. Methods. The specificity of the problem being solved determines the use of an analytical method for research, which allows us to consider the general scheme of the process flow, without specifying the dimensional characteristics. The research technique involves the compilation of differential equations of the motion of particles in a swirling air flow and determination of the trajectory of their movement. Results. The possibility and feasibility of using a direct-flow cyclone for dedusting ventilation emissions from an industrial premises before feeding to a heat recovery unit is considered. To assess the efficiency of dust cleaning, a mathematical description of the dynamics of motion of dust particles in a vortex flow of a direct-flow cyclone has been formulated. Analytical dependences are obtained, according to which the trajectories of motion of dust particles in projections onto the transverse and longitudinal planes of the cyclone body are calculated. The formulas obtained make it possible to determine the design and operating parameters of the dedusting device and to estimate the size of particles, the capture of which is provided by the proposed device. Conclusions 1. A rational layout diagram of a heat recovery system for ventilation air of industrial facilities has been determined, which in series connects a once-through cyclone with an impeller and a tube-plate heat exchanger. 2. A mathematical description of the dynamics of the motion of dust particles in a vortex flow has been formulated and investigated, and calculation formulas have been obtained for calculating the trajectories of motion of particles, which are used to determine the design and operating parameters of a direct-flow dust cleaner. Keywords: ventilation emissions, heat exchanger, dedusting of the air flow, direct-flow cyclone, particle trajectories.
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R.W. Mayes and H. Dove. "The use of n–alkanes and other plant–wax compounds as markers for studying the feeding and nutrition of large mammalian herbivores." BSAP Occasional Publication 34 (2006): 153–82. http://dx.doi.org/10.1017/s1463981500042400.
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SummaryIn the study of the feeding behaviour and nutrition of free-ranging mammalian herbivores, determining what the animals are eating, its quality and quantity can be difficult to accomplish. The measurement processes themselves may disturb the animals’ normal foraging behaviours which can be a major problem in rangeland, forest and other semi-natural environments. Furthermore, animals are likely to select mixtures of plants and their components which differ from the available vegetation. Quantitative measures of diet composition, digestibility, faecal output and intake in individual grazing or browsing animals have depended on the use of faecal markers. These are materials measurable in faeces that originate from the diet (internal markers), or are absent from the diet, but administered by oral dosing (external markers). The ‘ideal’ faecal marker needs complete recovery in faeces, simple and accurate quantitative measurement, inertness in having no effect on the animal or its diet, and similar physical characteristics (in terms of particle size and density) to the digestive tract contents. No individual material or chemical entity has been found which fulfils all of the ‘ideal’ marker attributes. For example, lignin, indigestible acid-detergent fibre (IADF) and ‘chromogen’, have been used as internal markers, but since they are not discrete compounds, analytical methods are empirical., resulting in inconsistent faecal recoveries.Virtually all higher plants have an outer surface layer of wax, which is usually a complex mixture of aliphatic lipid compounds whose composition differs between plant types, and different parts of the same plant. Plant waxes can be analysed as discrete compounds, are relatively inert, and because the patterns of individual compounds tend to differ between plant species, they offer the potential of enabling measurement of the contributions of specific plant species to the diet. Leaves and floral parts tend to have the highest concentrations; roots have very low levels. The main classes of plant waxes are straight and branched chain alkanes, alkenes, long–chain fatty acids and esters, long–chain fatty alcohols; long–chain fatty aldehydes and ketones and b–diketones. Analysis is usually carried out by a stepwise process of solvent extraction, purification and gas chromatography (GC). Straight–chain alkanes (n–alkanes) have been the most commonly used marker to date, being present as mixtures with chain lengths ranging from 21 to 37 carbon atoms. Over 90% of n–alkanes have odd–numbered carbon chains, with C29, C31and C33alkanes being dominant in most pasture species. Recovery in faeces of plant waxes is high but not complete, and is related to chain length, the longer the chain, the higher the recovery. Correction factors have been measured in a number of herbivore species.The first application of plant-wax n-alkanes as faecal markers was to determine herbage digestibility in ruminants. Subsequently it was realised that dosed synthetic alkanes could be used to determine faecal output, and hence dosed and herbage alkanes could be concurrently used to estimate intake. This offered substantial advantages over other methods. Furthermore, differences between plant species and parts in their patterns of individual alkanes can be exploited to enable quantitative determination of diet composition from the patterns found in faeces. Since differences in the relative faecal recoveries of individual markers could modify the faecal marker pattern, recovery corrections may be necessary. This approach was first used for measuring the composition of simple dietary mixtures and the intake of dietary supplements to be determined. The use of long-chain fatty alcohols and fatty acids as additional markers offers the potential for more complex diets to be evaluated. The fact that plant-wax alkanes remain attached to particulate dietary residues throughout the ruminant gut, means that they are also good markers for determining the rate of passage of material along the digestive tractEstimates of digestibility and faecal output obtained from respective natural and dosed n-alkanes will be biased, unless corrections are made to account for incomplete faecal recoveries. However, intake estimates will be unbiased if the faecal recoveries of the two markers are the same. Studies in sheep, cattle and goats have shown plant C33and dosed C32alkanes to have very similar faecal recoveries and thus give unbiased estimates of herbage intake. The alkane method for estimating intake offers advantages over other techniques. It gives individual-animal intakes and can be used where animals are receiving feed supplements. Also, GC analysis allows both plant and dosed markers to be determined at the same time, which limits analytical time, error and bias. Since the ratio of the concentrations in faeces is used, it is not necessary to obtain absolute faecal concentrations.Alkenes and branched-chain alkanes have been investigated as additional markers for diet composition estimation since they can be quantified in the same GC analysis asn-alkanes. Although alkenes, which tend to be associated with floral plant parts, have low recoveries (25-40%), they can be useful diet composition markers since their recoveries are little affected by chain length. Faecal recoveries of the branched-chain alkanes, fromAgrostis capillarisherbage, were slightly lower (60-65%) than the respectiven-alkanes (C30and C32) of equivalent carbon number (85-90%). These alkanes are rare in forage species, and their practical usefulness as markers for quantitative composition estimation has yet to be tested.Long-chain fatty alcohols have been shown to be effective diet composition markers. In most plants fatty alcohol concentrations are higher than those of hydrocarbons, and there can be profound differences in composition between species. They may be of particular value for diets containing plants with low alkane concentrations. Faecal recoveries in sheep, liken-alkanes, increase progressively with chain length from about 60% to 90%. It has been shown experimentally that the use of alcohols, together withn-alkanes, is likely to give a better estimate of diet composition in a given situation than n-alkanes alone.The very long-chain fatty acids of plant cuticular wax (C20-C34), originally suggested as digestibility markers, may also have potential as diet composition markers. Liken-alkanes and long-chain fatty alcohols, the faecal recoveries of plant-wax fatty acids in sheep increase with carbon chain length. Comparisons withn-alkanes and fatty alcohols suggested that the fatty acids were inferior as diet composition markers. This may have been due to the fact that the fatty acid extracts analysed by GC were relatively impure, containing a number of unidentified compounds. The reliability of plant-wax fatty acids as markers may be improved with more effective analytical procedures.There are a number of ways of calculating the diet composition from marker patterns in the faeces and potential dietary components. A simple approach is to determine a solution from a matrix of simultaneous equations; the number of dietary components must equal the number of markers used. Because, for simple dietary mixtures, there may be more available markers than dietary components, difficulties may arise in making the best choice of marker. Least-squares optimisation methods allow the number of markers to exceed the number of diet components, and thus (in theory) make better use of available information.Since the concept of using faecal marker patterns for making quantitative diet composition estimates is relatively new, the associated mathematical and statistical procedures used to date have been rather crude and simplistic. There is potential to make more effective use of the marker data by using more sophisticated computational approaches. These include a range of multivariate techniques, including: a) Principal component and discriminant analysis; b) The weighting of the contribution of different markers, since with the leastsquares optimisation procedure, markers with the highest overall concentrations contribute most to the composition estimate, even though some markers with low concentrations may have large relative differences between dietary components. It would logical to weight markers in favour of those having the greatest relative variation across dietary components, and those providing the least compositional information could be weighted against; c) Statistical procedures are needed to evaluate the quality of diet composition estimates. The minimisation procedures described earlier take no account of any within-component variation in marker composition, and the effect of such variation on the quality of resultant diet composition estimate is not known. Attempts are being made to develop statistical procedures which will provide details of confidence intervals of compositional estimates resulting from particular plant species mixtures of known within- and between-species variability in marker composition.For reliable estimation of digestibility, intake and diet composition, the feed sample must be representative, with respect to its plant wax marker concentration, of the material ingested by the animals under investigation, not necessarily all of the material present. Since marker concentrations can differ for different plant parts and plant species, care must be taken in sampling the vegetation for analysis. Although oesophageal-fistulated animals have been used to collect samples of ingested vegetation, hand-plucked grass samples have been found to be adequate for uniform grass swards,. In heterogeneous vegetation environments, especially when browse species are present, herbivores are likely to be highly selective. It is thus wise to make preliminary observations of animals’ ingestive behaviours, so appropriate parts of the dietary plants are sampled.The use of plant waxes, initially with alkanes, as markers in the study of the diets of domestic ruminants is finding increasing use in other herbivores, both domesticated and wild (moose, fallow deer, mountain hares, pigs, rabbits, horses, donkeys, giraffes). Such methodologies have been applied in non-mammalian herbivores, including birds (pigeons, and ostriches) and reptiles (tortoises). Synthetic alkanes have been used as markers to estimate digestibility and intake in fish. Although tests have not yet been carried out, plant wax marker methods may even be applicable to non-vertebrate herbivores, such as caterpillars, slugs and snails. Expansion of the technique to include plant wax compounds other than alkanes will broaden the spectrum of animals and systems which can and could be studied. Alkanes can be used to estimate the botanical composition of plant mixtures, including mixed root mats, and since these compounds can remain in soil for a considerable period, they may also be used to describe the vegetation history of an area by analysis of soil strata. There may be potential for this approach to be extended into archaeological and forensic studies. Insects and spiders contain hydrocarbons (mainly branched-chain alkanes) in their cuticular wax, and preliminary tests have indicated that these compounds are recoverable in the faeces of bats and insect-eating birds; thus they could be used to determine the insect species composition of the diets of insectivores. Analysis of these waxes is relatively simple, and although good GC equipment is required, there is scope for laboratories which do not posses the equipment to make the initial extractions and purification (simple but laborious), with the final GC analysis undertaken by a collaborating laboratory. Thus there are many uses of plant and animal waxes as markers, and potential applications are probably limited only by our imagination.
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Yang, Yong, and Xiaochun Li. "Ultrasonic Cavitation Based Nanomanufacturing of Bulk Aluminum Matrix Nanocomposites." Journal of Manufacturing Science and Engineering 129, no. 3 (February 5, 2006): 497–501. http://dx.doi.org/10.1115/1.2714583.
Full textAbstract:
Lightweight metal–matrix nanocomposites (MMNCs) (metal matrix with nanosized ceramic particles) can be of significance for automobile, aerospace, and numerous other applications. It would be advantageous to develop effective nanomanufacturing methods for fabrication of bulk components of aluminum based MMNCs through solidification processing. However, it is extremely difficult to disperse nanosized ceramic particles uniformly in molten aluminum. In this paper, a high power ultrasonic probe is used to disperse nanosized SiC particles into molten aluminum alloy A356. Experimental results show that the ultrasonic cavitation based dispersion of nanoparticles in molten aluminum alloy is effective. The uniform nanoparticle dispersion in the Al alloy matrix resulted in significantly improved mechanical properties. To enhance the nanomanufacturing efficiency, various nanoparticle feeding techniques were explored and experimental results are presented.
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Yang, Yong, and Xiaochun Li. "Ultrasonic Cavitation-Based Nanomanufacturing of Bulk Aluminum Matrix Nanocomposites." Journal of Manufacturing Science and Engineering 129, no. 2 (February 5, 2006): 252–55. http://dx.doi.org/10.1115/1.2194064.
Full textAbstract:
Lightweight metal matrix nanocomposites (MMNCs) (metal matrix with nanosized ceramic particles) can be of significance for automobile, aerospace, and numerous other applications. It would be advantageous to develop effective nanomanufacturing methods for fabrication of bulk components of aluminum-based MMNCs through solidification processing. However, it is extremely difficult to disperse nanosized ceramic particles uniformly in molten aluminum. In this paper, a high power ultrasonic probe is used to disperse nanosized SiC particles into molten aluminum alloy A356. Experimental results show that the ultrasonic cavitation based dispersion of nanoparticles in molten aluminum alloy is effective. The uniform nanoparticle dispersion in the Al alloy matrix resulted in significantly improved mechanical properties. To enhance the nanomanufacturing efficiency, various nanoparticle feeding techniques were explored and experimental results are presented.
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Labisz, Krzysztof, and Tomasz Tański. "Laser Surface Treatment of Cast Aluminium-Silicon Alloys." Solid State Phenomena 275 (June 2018): 30–40. http://dx.doi.org/10.4028/www.scientific.net/ssp.275.30.
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The reason of performing the investigations carried out in this work was to investigate the microstructure of the laser treated Al-Si-Cu cast aluminium alloy with the ceramic powder particles using High Power Diode Laser (HPDL) for remelting, and/or alloying. First of all the feeding and distribution of the powder in the surface layer of the alloyed and remelted AlSi7Cu material. Very important issue is the determination of the laser treatment parameters, especially the powder feeding rate, laser power, and scan rate to achieve an enhancement of the layer hardness for ensuring this cast aluminium alloy from losing their working properties and to achieve the tool surface is more resistant to wear. The purpose of this work was also to determine technological and technical conditions comparison for the Al2O3 and SiC ceramic powder alloyed into the surface layer with High Power Diode Laser. There are presented also the investigation results about the determination of proper technical condition during the laser treatment, especially the laser head distance and shielding gas influence. The presented results concerns first of all the structure investigation of the obtained surface layer allowing it to achieve an enhanced hardness and wear resistance more resistant for work, special attention was devoted to monitoring of the layer morphology of the investigated material and on the particle occurred. Light (LM) and scanning electron microscopy (SEM) were used to characterize the microstructure of the obtained surface zones - the remelted zone (RZ) and heat affected zone (HAZ), the ceramic powder distribution and intermetallic phases occurred. A wide range of laser power values was applied and implicated with different laser scan rates. The powders in form of ceramic powders used for alloying were chosen with the particle size of ca. 60μm. This study was conducted to investigate the influence carbide and oxide powder addition on structure and mechanical properties as well the and structure changes occurred during the rapid solidification process. The investigation ensures to use laser treatment for alloying/feeding of ceramic powder particles into the surface of light alloys. The scientific reason of this work is the applying of High Power Diode Laser (HPDL) for improvement of aluminium`s mechanical properties, especially the surface hardness. As the main findings was determined that the obtained surface layer is homogeny without cracks and has a comparably higher hardness value compared to non-treated material. The surface hardness increases together with the applied laser power, the highest power applied gives the highest hardness value for the surface. Also the distribution of the ceramic particles is proper, but there a need for further modelling, because the hardness increases in general according to the laser power used so that the highest power applied gives to highest hardness value in the remelted layer, but for other powder amount or alloy the values should be determined separately, and more data would be necessary to create a model for the technique appliance. The practical purpose of this work is to analysis the impact and application possibility of HPDL laser surface treatment on the cast Al-Si-Cu alloys to deliver application possibilities for diverse branches of industry.
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Wang, Y., T. A. McAllister, L. M. Rode, K. A. Beauchemin, D. P. Morgavi, V. L. Nsereko, A. D. Iwaasa, and W. Yang. "Effects of an exogenous enzyme preparation on microbial protein synthesis, enzyme activity and attachment to feed in the Rumen Simulation Technique (Rusitec)." British Journal of Nutrition 85, no. 3 (March 2001): 325–32. http://dx.doi.org/10.1079/bjn2000277.
Full textAbstract:
The effects of an exogenous enzyme preparation, the application method and feed type on ruminal fermentation and microbial protein synthesis were investigated using the rumen simulation technique (Rusitec). Steam-rolled barley grain and chopped alfalfa hay were sprayed with water (control, C), an enzyme preparation with a predominant xylanase activity (EF), or autoclaved enzyme (AEF) 24 h prior to feeding, or the enzyme was supplied in the buffer infused into the Rusitec (EI). Microbial N incorporation was measured using (15NH4)2SO4in the buffer. Spent feed bags were pummelled mechanically in buffer to segregate the feed particle-associated (FPA) and feed particle-bound (FPB) bacterial fractions. Enzymes applied to feed reduced neutral-detergent fibre content, and increased the concentration of reducing sugars in barley grain, but not alfalfa hay. Ruminal cellulolytic bacteria were more numerous with EF than with C. Disappearance of DM from barley grain was higher with EF than with C, but alfalfa was unaffected by EF. Treatment EF increased incorporation of15N into FPA and FPB fractions at 24 and 48 h. In contrast, AEF reduced the 24 h values, relative to C; AEF and C were similar at 48 h. Infused enzyme (EI) did not affect15N incorporation. Xylanase activity in effluent was increased by EF and EI, compared to C, but not by AEF. Xylanase activity in FPA was higher at 48 h than at 24 h with all treatments; it was higher with EF than C at 24 and 48 h, but was not altered by AEF or EI. Applying enzymes onto feeds before feeding was more effective than dosing directly into the artificial rumen for increasing ruminal fibrolytic activity.
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Fry, Kenneth M., and Douglas A. Craig. "Larval black fly feeding (Diptera: Simuliidae): use of endogenous glycoconjugates." Canadian Journal of Zoology 73, no. 4 (April 1, 1995): 615–22. http://dx.doi.org/10.1139/z95-072.
Full textAbstract:
Histochemical techniques were used to determine the origin and possible function of glycoconjugates in the head region of larval black flies. Late-instar larvae of Simulium vittatum Zetterstedt and Gymnopais dichopticoides Wood were stained with Alcian blue at pH 0.5, 2.5, and 3.2, aldehyde fuchsin, and periodic acid – Schiff's reagent to determine the chemical affinities of the glycoconjugates. Additionally, larvae were fed inert Dayglo® particles and then sectioned and stained as above to determine the origin of glycoconjugates observed in the gut contents and on the labral fan rays. Examination showed that carboxylated and weakly sulphated glycoconjugates are secreted from what are redescribed here as dorsal and ventral cephalic glands. These glands are associated with the labral, mandibular, hypostomal, and maxillary epidermis. The secretion product is not used to enhance food capture or handling. Instead, it is hypothesized that these glycoconjugates aid in formation of mouthpart structures during the pharate stages, or facilitate ecdysis. Glycoconjugates, previously observed in the gut and on the surface of the mouthparts, must be of exogenous origin.
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Song, Zhuguo, and Hui Li. "Plasma Spraying with Wire Feeding: A Facile Route to Enhance the Coating/Substrate Interfacial Metallurgical Bonding." Coatings 12, no. 5 (April 30, 2022): 615. http://dx.doi.org/10.3390/coatings12050615.
Full textAbstract:
Thermal spray coatings are widely used in many applications, and the adhesion effect at the coating/substrate interface plays an important role during the service life. The thermal spraying coating and substrate is primarily combined by a mechanical seizure effect. In this work, a strategy to generate interfacial metallurgical bonding is proposed. Plasma spraying with wire feeding was adopted to increase the size of sprayed particles, and metallurgical bonding was clearly formed between deposited particles and the substrate (304 stainless-steel and 7075 aluminum alloy). Interface reaction can be found at both NiAl/7075 and NiAl/304 interfaces. Typical Al-Al3Ni eutectic phase with higher microhardness was formed at NiAl/7075 interface. The adhesive strength of the coatings was significantly improved to 82.67 ± 3.96 MPa and 64.45 ± 2.84 MPa, respectively, for NiAl coating on 304 and 7075 substrates through tensile adhesion tests (TAT) without surface roughening pretreatment. This technique shows a promising aspect of the application of thermal spray coatings.
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Waran, N. K., and D. M. Broom. "Evidence of the ineffectiveness of creep-feeding using a new method for measuring intake by early-weaned piglets." Proceedings of the British Society of Animal Production (1972) 1992 (March 1992): 17. http://dx.doi.org/10.1017/s0308229600021425.
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Little is known about how creep-feeding influences later growth rate in pigs. In previous studies, creep-food consumption has been measured by limiting access to food to allow the time spent feeding by individuals to be measured, however there are problems with this approach. Competition for the feeder may result in inaccurate measurement since some piglets may not have the opportunity to feed. Also, piglets will have less opportunity to learn about the food source by observing others. The approach used in the current experiment gave all piglets access to creep-food at the same time, allowing the piglets to feed normally. Any synchronisation in feeding activity that might affect food consumption was possible. Five litters of Large White X Landrace piglets were offered a home-mix starter diet from 10 days of age. A mark and capture technique was employed. The inert marker (Microtracer RF-Ni; Guinness Chemicals Ltd.) was mixed with the diet (30 g/tonne) that was fed to the piglets. The microtracer was a ferro-magnetic alloy powder of minute particle size (25,000 parts/gramme), that resisted dissolution in the gastrointestinal tract and was easily recovered from a faeces-water slurry using a magnetic ‘wand’. Faeces were collected from piglets at 18 days of age. Piglets were weaned at 21 days and were randomly allocated to one of four types of weaner pen, where they remained for 4 weeks. Weaned piglets were fed the starter diet ad lib for 7 days after which they were fed a standard weaner diet. On average 1.9 g (dry matter weight) of faeces were collected from each piglet. The number of particles retrieved from faecal samples (mean = 5.4, range = 0 - 39), and the proportion of iron particles per gramme of dried faeces was calculated for each piglet that was sampled, as an estimate of creep-feed intake. There was a large variation among piglets in creep-feed intake but no significant difference between litters. Females consumed more creep-feed than males (p < 0.001, t-test) (Fig. 1), but experienced the same growth check as males post-weaning. There was no relationship between weight gain post-weaning and creep-feed intake. It was concluded that creep-food consumption, measured using this method, did not influence weight gain post-weaning. This method may be used in association with other methods of measuring creep-food consumption, such as measuring lime-spent at the feeder, to give a more accurate estimate of individual creep-food consumption.
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Tankersley, Richard A., and Ronald V. Dimock Jr. "Endoscopic visualization of the functional morphology of the ctenidia of the unionid mussel Pyganodon cataracta." Canadian Journal of Zoology 71, no. 4 (April 1, 1993): 811–19. http://dx.doi.org/10.1139/z93-106.
Full textAbstract:
During reproduction, the outer demibranchs of the unionid mussel Pyganodon cataracta serve as marsupia, with incubation of the developing shelled glochidia larvae occurring within the water tubes. In this study, recently developed endoscopic video analysis techniques were employed to examine in vivo the dynamics of filter feeding and water transport in mussels during gravid and postgravid periods. Particles entering the mantle cavity and retained by the gills were transported to the palps in a complex mucus-bound cord by the ventral food groove of the medial ctenidia. Larval incubation and ctenidial swelling impeded flow around the lateral demibranchs, although marsupial ctenidia were still actively involved in suspension feeding. Cilia on the distended ventral edges of marsupial demibranchs were often observed transporting filtered particles to the frontal surface of the medial gills. Larvae within the brood chambers were morphologically isolated from the surrounding medium by dorsal brood caps on the primary water tubes. Direct observations of the secondary water tubes of marsupial gills constructed during periods of larval incubation confirmed their role as temporary lumina for water transport during gravid periods. Time-lapse video recordings revealed that mature larvae are released from the brood chambers via the suprabranchial cavity and exhalant siphon by rapid adductions of the valves and contractions of the brooding demibranchs.
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brunnschweiler, juerg m., paul l. r. andrews, emily j. southall, mark pickering, and david w. sims. "rapid voluntary stomach eversion in a free-living shark." Journal of the Marine Biological Association of the United Kingdom 85, no. 5 (October 2005): 1141–44. http://dx.doi.org/10.1017/s0025315405012208.
Full textAbstract:
video observation of oral gastric eversion in a free-living caribbean reef shark (carcharhinus perezi) shows voluntary gastric eversion followed by retraction not only occurs, but is extremely rapid (lasting ∼0.3 s). eversion may occur by stomach relaxation–oesophageal contraction coupled with increased abdominal pressures to enable prolapse, and retraction by a mechanism analogous to suction feeding. this behaviour provides a ‘cleansing’ function for removing indigestible food particles, parasites or mucus from the stomach lining. sharks, and possibly other animals with similar gut morphologies, may use this technique to help maintain a healthy alimentary tract.
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Hamawand, Ihsan, Wilton Pereira da Silva, Friederike Eberhard, and Diogenes L. Antille. "Issues related to waste sewage sludge drying under superheated steam." Polish Journal of Chemical Technology 17, no. 4 (December 1, 2015): 5–14. http://dx.doi.org/10.1515/pjct-2015-0062.
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Abstract Sewage sludge was dried in a rotary drum dryer under superheated steam. Particle size and moisture content were shown to have significant influences on sticking and agglomeration of the materials. Pouring partially dried sludge (70–80% moisture content, wet basis) directly into the screw feeder of the drum dryer resulted in a significant sticking to the surface of the drum and the final particle size of the product was greater than 100 mm in diameter. The moisture content of this product was slightly less than its initial value. To overcome this issue, the sludge was mixed with lignite at variety ratios and then chopped before being introduced to the feeding screw. It was found that mixing the sludge with lignite and then sieving the chopped materials through a four millimetre mesh sieve was the key to solve this issue. This technique significantly reduced both stickiness and agglomeration of the material. Also, this enabled for a significant reduction in moisture content of the final product.
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Yufera, M., MC Sarasquete, and C. Fernandez-Diaz. "Testing protein-walled microcapsules for the rearing of first-feeding gilthead sea bream (Sparus aurata L.) Larvae." Marine and Freshwater Research 47, no. 2 (1996): 211. http://dx.doi.org/10.1071/mf9960211.
Full textAbstract:
Two basic types of protein-walled microcapsules were developed with the aid of using different preparation techniques. One type (Type A) was spherical and hard-walled, whereas the other (Type G) was irregularly shaped and soft-walled. The present work examined the larval growth and development of Sparus aurata reared either with these microcapsules as the sole food source or with a mixed diet of microcapsules and rotifers from the start of feeding. Larvae fed on Type A microcapsules evacuated them practically intact. These larvae showed strong degeneration of the gut epithelium, liver and pancreas and died within two to three days after the onset of feeding. In contrast, larvae fed from first feeding with Type G microcapsules alone ingested and broke down the particles from the onset of feeding. No larval growth was observed, but some larvae were still alive at the end of the experiment (Day 13). Larvae reared with a mixed diet, including Type G microcapsules and a small amount of rotifers (0.5 rotifer mL-1), showed in general normal development of gut epithelium. These larvae had good growth but survival was reduced to one-half of that obtained under routine rearing of larvae fed on rotifers alone. Type G microcapsules appear to represent an adequate departure point for the development of an inert diet able to support larval growth in marine fish.
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THIEN, DOAN VAN HONG, SHENG WEN HSIAO, and MING HUA HO. "SYNTHESIS OF ELECTROSPRAYED CHITOSAN NANOPARTICLES FOR DRUG SUSTAINED RELEASE." Nano LIFE 02, no. 01 (March 2012): 1250003. http://dx.doi.org/10.1142/s1793984411000360.
Full textAbstract:
Chitosan (CS) nanoparticles for drug delivery were fabricated by an electrospraying method. The effects of CS molecular weight on electrospraying were investigated. The size and morphology of CS particles were strongly influenced by CS molecular weight. Besides, CS concentration, electrical field, acetic acid concentration, and solution feeding rate in the electrospraying process were also studied. To evaluate the potential of electrosprayed CS nanoparticles in drug delivery, indomethacin (ID) was used as a model drug, where the encapsulation efficiency, the loading capacity, and the releasing profiles were identified. The CS-ID spherical nanoparticles were fabricated by the electrospraying technique, with the average diameter of 340 nm. Zeta potential of the ID-CS particles indicated that the particles were stable in the suspension. The encapsulation efficiency (EE) and loading capacity (LC) of ID were higher for 150-kDa CS than for 310-kDa CS. The EE of ID in electrosprayed CS particles was higher than that in particles prepared by other methods. The release profiles revealed that there were two stages for releasing and the long-term delivery could be obtained in the second stage. In summary, this research optimized the electrospraying process for the fabrication of CS nanoparticles and demonstrated the potential of electrosprayed CS nanoparticles as a drug carrier.
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Mould, F. L., R. M. Mauricio, T. Smith, and E. Owen. "The influence of rumen fluid pH on the rate and extent of maize silage and wheat straw degradation estimated in vitro using the Reading Pressure Technique." Proceedings of the British Society of Animal Science 2000 (2000): 53. http://dx.doi.org/10.1017/s1752756200000545.
Full textAbstract:
Fermentation of the increasingly energy-dense rations offered to meet the nutrient demands of today's high yielding dairy cows ought to adversely rumen fibre degradation. Not only could rumen fluid pH be depressed below that assumed critical to cellulolysis for extended periods of time but the quantity of readily fermentable carbohydrate available will further exacerbate this effect. These, together with the reduced rumen retention time of feed particles associated with high feeding levels could significantly limit fibre degradation. This in vitro study was designed to identify the pH at which degradation becomes impaired, the extent of this depression and whether the effect varies according to the feedstuffs offered.
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Kra¨upl, Stefan, and Aldo Steinfeld. "Pulsed Gas Feeding for Stoichiometric Operation of a Gas-Solid Vortex Flow Solar Chemical Reactor." Journal of Solar Energy Engineering 123, no. 2 (November 1, 2000): 133–37. http://dx.doi.org/10.1115/1.1351172.
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The thermodynamic implications of conducting the solar combined ZnO-reduction and CH4-reforming under stoichiometric and non-stoichiometric conditions are examined. For a solar flux concentration ratio of 5000 and for a solar cavity-receiver operating at 1300 K, the solar thermal conversion efficiency is 55 percent for a stoichiometric molar ratio of ZnO and CH4, and decreases by 50 percent when using excess methane by a factor 10 over the stoichiometric molar amount. A technical solution for operating a gas-solid vortex-flow solar reactor under stoichiometric conditions was established by using a pulsed-feed of methane to carry out the particles of ZnO. Using this technique, nearly stoichiometric operation was demonstrated with a prototype reactor in a high-flux solar furnace, thereby opening up a means for efficient conversion of sunlight into chemical fuels.
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Amar, Arun P., George P. Teitelbaum, and Donald W. Larsen. "A Novel Technique and New Grading Scale for the Embolization of Cerebral Vascular Malformations." Neurosurgery 59, suppl_5 (November 1, 2006): S3–18—S3–162. http://dx.doi.org/10.1227/01.neu.0000237518.36683.6a.
Full textAbstract:
Abstract OBJECTIVE: Effective transarterial embolization of a dural arteriovenous fistula or pial arteriovenous malformation (AVM) requires penetration of a durable occlusive agent into the fistula or AVM nidus. Cyanoacrylate glue often cannot traverse the tortuous vessels that typically supply such malformations, leading to proximal occlusion and recruitment of collateral flow. Other embolic agents, such as polyvinyl alcohol particles, achieve better penetration, but their effects are short lived, often leading to recanalization. The authors sought to overcome these obstacles by developing a technique to enhance glue penetration into the fistula or AVM nidus itself. METHODS: After placing a guide catheter in the proximal feeding artery, a microcatheter is advanced coaxially to its limit. As glue is injected through the microcatheter, a column of 5% dextrose in water (D5W) is pushed manually through the guide catheter lumen to propel the glue forward. This technique has been bench tested in a standard flow model of vascular malformations, using a pump capable of delivering various rates of D5W. It has also been validated in treating 17 patients with cerebral dural arteriovenous fistulae or AVMs, with real-time adjustment of D5W flow according to the extent of glue penetration. RESULTS: In the bench model, the extent of glue penetration, as graded by a new scale of liquid agent embolization proposed by the authors, correlated directly with the rate of D5W flow (P = 0.5, analysis of variance). In vivo, this technique has enhanced the penetration of glue into the fistula or AVM nidus, resulting in longstanding embolization of these malformations. CONCLUSION: Coaxial injection of D5W through the guide catheter can propel cyanoacrylate glue through tortuous feeding arteries and can enhance its penetration into dural fistulae and AVMs, leading to more effective endovascular treatment of these malformations.
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Fry, Kenneth M. "Endogenous glycoconjugates are not associated with filter feeding in mosquito larvae (Diptera: Culicidae)." Canadian Journal of Zoology 74, no. 3 (March 1, 1996): 413–22. http://dx.doi.org/10.1139/z96-048.
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Histochemical techniques were used to determine the origin and possible function of glycoconjugates in the head of larval mosquitoes. Late instars of Aedes aegypti (L.), Aedes implicatus Vockeroth, Culex territans Walker, and Anopheles earlei Vargas were stained with Alcian Blue at pH 0.5, 2.5, and 3.2, aldehyde fuchsin, and periodic acid – Schiff's reagent. Lectins derived from Triticum vulgaris, Bandeiraea simplicifolia, Sophora japonica, Pisum sativum (PSA), and Ulex europaeus were used to determine the composition of the glycoconjugates present in the head of A. aegypti. Additionally, larvae were fed inert Dayglo® particles and stained as above to determine the origin of glycoconjugates observed in the gut. Examination showed that carboxylated and weakly and strongly sulphated glycoconjugates are secreted from what are described here as dorsal and ventral cephalic glands. With the exception of PSA, none of the lectins bound to the glands or their secretion product. Globular and elongate cells in the ventral cephalic gland bound PSA, indicating the presence of α-D-mannose. The secretion product is not used to enhance food capture or handling. Instead, it is hypothesized that these glycoconjugates aid in formation of mouthpart structures or facilitate ecdysis.
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Wilson, S. C., J. Morrow-Tesch, D. C. Straus, J. D. Cooley, W. C. Wong, F. M. Mitlöhner, and J. J. McGlone. "Airborne Microbial Flora in a Cattle Feedlot." Applied and Environmental Microbiology 68, no. 7 (July 2002): 3238–42. http://dx.doi.org/10.1128/aem.68.7.3238-3242.2002.
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ABSTRACT A total of 1,408 cattle held in eight commercial feedlot pens were used to examine the quantity and diversity of microorganisms in cattle feedlot air. The effect of two feeding patterns on the generation of airborne dust and the total numbers of microorganisms was also examined (four feedlot pens/treatment). Microbial samples were collected, and dust particles that were 2.5 μm or less in diameter were measured with a Dustrak monitor during the evening dust peak for 4 days at sites both upwind and downwind of the feedlot pens. An Andersen biological cascade sampler was employed with different medium and incubation combinations for the capture and identification of bacteria and fungi. The results showed that when bacteria were considered, only nonpathogenic gram-positive organisms were recovered. However, gram-negative bacteria may have been present in a viable but nonculturable state. Fungi were recovered in smaller numbers than bacteria, and none of the fungi were pathogenic. The Dustrak results showed that one feeding pattern resulted in cattle behavior that generated levels of downwind dust lower (P = 0.04) than the levels generated by the behavior resulting from the other feeding pattern. However, the Andersen sampler results showed that there were no differences between feeding patterns with regard to the total number or diversity of microorganisms. The disparity may have been due to the different operating principles of the two systems. The overall numbers of microorganisms recovered were lower than those reported in studies of intensively housed farm animals in which similar recovery techniques were used.
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Kandemir, Sinan, Anurag Yalamanchili, and Helen V. Atkinson. "Production of Aluminium Matrix Nanocomposite Feedstock for Thixoforming by an Ultrasonic Method." Key Engineering Materials 504-506 (February 2012): 339–44. http://dx.doi.org/10.4028/www.scientific.net/kem.504-506.339.
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Metal matrix nanocomposites (MMNCs) could be strong candidates for use in the automotive and aerospace industry, where the mechanical performance is a crucial factor. This study aims to determine the feasibility of Al/SiC nanocomposite fabrication by the ultrasonic technique for the production of thixoforming feedstock material. Aluminium (A356) matrix composites were fabricated with the addition of 0.2 wt.% SiC nanoparticles using an ultrasonic method. Two different particle feeding mechanisms; the Al foil double capsulate method and the crucible placement approach, were employed. Better results were obtained for the double capsulate method. Also, Ti and Nb probe tips were tried to provide ultrasonic vibration in the melt. It has been shown that Nb is a promising ultrasonic probe tip material to produce MMNCs above 650 °C as it is thermodynamically stable in comparison with Ti.
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Bal, Trishna, Shubhranshu Sengupta, and Padala Narasimha Murthy. "Formulation and evaluation of carvedilol microcapsules using Eudragit NE30D and sodium alginate." Brazilian Journal of Pharmaceutical Sciences 49, no. 4 (December 2013): 889–901. http://dx.doi.org/10.1590/s1984-82502013000400029.
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Inclusion complexes of carvedilol(CR) with hydroxyl propyl beta-cyclodextrin (HPBCD) was prepared using co-grinding technique. Then, the inclusion complex was microencapsulated using combinations of Eudragit NE30D (EU) and sodium alginate (SA) utilizing orifice gelation technique. The formulations were analysed by using Scanning electron microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), Differential scanning Calorimetry (DSC) and X-ray diffractometer (XRD) and also evaluated for particle size, encapsulation efficiency, production yield, swelling capacity, mucoadhesive properties, zeta potential and drug release. The microcapsules were smooth and showed no visible cracks and extended drug release of 55.2006% up to 12 hours in phosphate buffer of pH 6.8, showing particle size within the range of 264.5-358.5 µm, and encapsulation efficiency of 99.337±0.0100-66.2753±0.0014%.The in vitro release data of optimized batch of microcapsules were plotted in various kinetic equations to understand the mechanisms and kinetics of drug release, which followed first order kinetics, value of "n" is calculated to be 0.459 and drug release was diffusion controlled. The mice were fed with diet for inducing high blood pressure and the in vivo antihypertensive activity of formulations was carried out administering the optimized formulations and pure drug separately by oral feeding and measured by B.P Monwin IITC Life Science instrument and the results indicated that the bioavailability of carvedilol was increased both in vitro and in vivo with the mucoadhesive polymers showing primary role in retarding the drug release.
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Gregory, P. C., M. Mcfadyen, and D. V. Rayner. "Pattern of gastric emptying in the pig: Relation to feeding." British Journal of Nutrition 64, no. 1 (July 1990): 45–58. http://dx.doi.org/10.1079/bjn19900008.
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The aims of the present study were to compare the gastric emptying of dry matter (DM) and liquids during the feeding period with that following meal consumption, to clarify the relationship between feeding and gastric emptying, and to investigate how gastric emptying changes in growing animals. The studies were performed in pigs fitted with a gastric cannula and fed on a normal finely ground solid diet mixed with water containing CrEDTA as liquid marker. Gastric emptying was measured using a gastric evacuation technique. It was observed that between 0.75 and 6 h after feeding the total amounts emptied increased, but the proportion of the meal emptied fell, with increase in meal size; emptying of both DM and liquids with large and small meals followed and exponential pattern. In contrast, while the animals were feeding, there was linear and rapid emptying of both DM and liquids following a very short (approximately 2 min) lag phase before emptying began. The rate of emptying increased linearly with body-;weight (by 0.55 g DM/min and by 0.24 ml/min per kg body-weight over the range 58–200 kg) such that the emptying of digestible energy per kg metabolic body-weight (W0.75) was roughly maintained (between 2.9 and 3.2 kJ/min per kg W0.75). This suggests that the rate of emptying may be linked in some way with the metabolic requirements of the body. The biphasic pattern of gastric emptying observed is probably the intrinsic pattern of emptying of a meal which does not require breakdown of particles before emptying can occur.
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Jia, Zhen-Yu, Chun-Gao Zhou, Jin-Guo Xia, Lin-Bo Zhao, Wen Zhang, Sheng Liu, and Hai-Bin Shi. "Endovascular Treatment of 12 Cases of Renal Arteriovenous Malformations: The Experience of 1 Center and an Overview of the Literature." Vascular and Endovascular Surgery 52, no. 1 (November 12, 2017): 46–51. http://dx.doi.org/10.1177/1538574417740509.
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Objectives: Congenital renal arteriovenous malformations (rAVMs) represent rare vascular diseases. The heterogeneous vascular architecture of each rAVM determines the endovascular treatment techniques employed. We reported our experience with the endovascular treatment of a series of rAVMs. Materials: This retrospective study consisted of 12 patients with 12 rAVMs who underwent renal arterial embolization (RAE) in our hospital. Embolic materials, including particles, liquid embolic agents (n-butyl 2-cyanoacrylate, Onyx, and ethanol), and coils, were selectively used based on the decisions of interventional radiologists. Technical success was defined as the complete occlusion of the feeding arteries and nidus on postprocedure renal arteriography. Clinical success was defined as the resolution of hematuria or the disappearance of rAVM-relevant symptoms. Results: The median follow-up period was 13.5 months (range: 4-72). The technical success based on 12 procedures in 12 patients was 83.3% (10 of 12). In the 2 procedures that technically failed, the existence of multiple fine feeding arteries arising from the proximal portion of different segmental renal arteries explains the incomplete embolization. One of the 2 patients achieved clinical success without additional RAE. The other patient had recurrent hematuria 25 months after initial treatment, which was successfully managed conservatively with hemostatic agents. Thus, the clinical success was 91.7% (11 of 12). Conclusions: Renal artery embolization with the selective use of various embolic materials is an effective treatment for patients with rAVMs. The existence of multiple fine feeding vessels arising from the proximal portion of different segmental renal arteries is likely to affect the technical success of treatment.
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CANDIOTI, M. FLORENCIA VERA. "Anatomy of anuran tadpoles from lentic water bodies: systematic relevance and correlation with feeding habits." Zootaxa 1600, no. 1 (September 28, 2007): 1–175. http://dx.doi.org/10.11646/zootaxa.1600.1.1.
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I studied anatomy, gut content, and the relationship among these traits in a set of anuran tadpoles. Larval stages (mainly Gosner stages 31–36) of nineteen species from various lentic environments were selected. Morphological characters from the skeleton, musculature, oral apparatus and buccopharyngeal cavity were recorded, and a gut content analysis was performed, with emphasis on food size distribution. Ordination techniques were applied in order to find patterns of similarity in morphology and gut content. Canonical ordination methods were used to investigate the relationship among gut content, morphology, and phylogeny in the species considered. The results show that several skeletal, muscular, and buccal characters are relatively maintained within genera. Other features, which have appeared independently in different lineages, reflect convergence phenomena in some cases related to ecological aspects. The configuration of the hyobranchial skeleton, the development of the buccal floor depressor and levator muscles, and mouth gape width correlate with prey size. In some species, morphology is clearly related with feeding. Tadpoles that ingest large food particles relative to their body length present morphological traits attributable to macrophagy. Taxonomically unrelated tadpoles of Dendropsophus nanus, D. microcephalus and Ceratophrys cranwelli possess hyobranchial skeletons with robust, rostrocaudally long ceratohyals and reduced branchial baskets with short ceratobranchials devoid of lateral projections and spicules. Lepidobatrachus llanensis tadpoles have laterally extended ceratohyals which, along with the lateral extension of the jaws, result in a very wide oral apparatus and an ample buccopharyngeal cavity that allows the tadpole to ingest large and whole prey; the branchial basket, although its ceratobranchials lack lateral projections and spicules, is slightly reduced in area. The four species mentioned have a noticeable development of the buccal floor depressor muscles, and buccal cavities with scarce filtering and entrapping structures. In Elachistocleis bicolor, Dermatonotus muelleri, Chiasmocleis panamensis, and Xenopus laevis tadpoles, the branchial basket occupies >70% of the total hyobranchial skeleton area, and the hypobranchial plates are highly reduced; the buccal floor levator muscles are well-developed, with an increased site of attachment on the ventral expansion of the lateral process of the ceratohyal; the scarcity of the filtering structures in the buccopharyngeal cavity are balanced with the great development of the branchial filters and secretory zones; all these features relate to a diet based on small particles not significantly different from those of most other species; however, experimental studies show that species with similar hyobranchial apparatus and muscles are the most efficient when retaining minute particles. Finally, a large group of species present generalized morphological characters, such as a branchial basket occupying about 50% of the total hyobranchial apparatus, intermediate values of mouth gape width and buccal floor levator / depressor muscles ratio, and abundant filtering structures in the buccopharyngeal cavity; these species feed frequently on food particles between 1–30% of the tadpole body length; however, in some of the species, macrophagous diets are also reported in the literature, indicating that this morphology is flexible in more ample prey size ranges.
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Martínez-Flores, Héctor E., Eunice Tranquilino-Rodríguez, José O. Rodiles-López, and Guillermo C. G. Martínez-Avila. "Nanoencapsulation and identification of phenolic compounds by UPLC-Q/TOF-MS2 of an antioxidant extract from Opuntia atropes." Functional Foods in Health and Disease 10, no. 12 (December 31, 2020): 505. http://dx.doi.org/10.31989/ffhd.v10i12.763.
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Background: Nanoencapsulation is a technique that protects bioactive compounds such as polyphenolic compounds from environmental factors, through a biopolymer that acts as a wall system. Cladodes of O. atropes are an important source of polyphenolic compounds, flavonoids being the most abundant, these are mainly in the form of glycosides and their consumption has been related to a decrease in glucose and lipid profile through the elimination of intracellular radicals.Purpose of the study: To study the formulation and process parameters that allow obtaining the best experimental conditions to nanoencapsulation and protect the polyphenolic compounds of the O. atropes extract.Methods: Wall materials applied for nanoencapsulation (soy protein isolate, calcium caseinate , and maltodextrin). A Box Behnken 33 design was used; wall material extract of O. atropes (1/1, 2.5 / 1, 4/1), temperature (95, 105 and 115 ° C) and spray (40, 70 and 100%), to evaluate the yield, feeding speed, particle size, encapsulation efficiency, phenolic acids, flavonoids, DPPH• and ABTS•+. Polyphenolic compounds were identified by UPLC-Q / TOF-MS2.Results: Maltodextrin presented better properties in the encapsulation of the extract of O. atropes. The Box Behnken 33 design made it possible to identify the treatment with the appropriate quality characteristics for the nanoencapsulation process; Formulation 2.5 / 1 (maltodextrin / O. atropes extract), 115 ° C and 100% spray, to obtain 85.22% yield, feeding speed of 9 mL / h, the particle size of 154.77 nm, 55.69 % encapsulation efficiency, phenolic acids of 0.95 mg GAE / g, flavonoids of 7.02 mg QE / g, and antioxidant activity in DPPH• of 0.29 mg GAE / g and ABTS•+ of 0.45 mg GAE / g. The polyphenolic profile was characterized, and it was confirmed that nanoencapsulation protects some isomers of isorhamnetin 3-O-rhamnosido-7-O- (rhamnosyl-hexoside) and p-coumaric acid 4-O-glucoside.Conclusion: Maltodextrin is an excellent encapsulating material of the O. atropes extract, the formulation and process conditions that favored all the response variables were identified and it was shown that nanoencapsulation protects the polyphenolic compounds.Keywords: O. atropes extract, nanoencapsulation, polyphenolic profile, UPLC-Q / TOF-MS2.
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Shadi, Maryam, and Zahra Atlasbaf. "Randomly overlap subarray feeding network to reduce number of phase shifter in 28GHz." PLOS ONE 17, no. 12 (December 8, 2022): e0277404. http://dx.doi.org/10.1371/journal.pone.0277404.
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Synthesizing antenna arrays for fifth-generation communication technology is the most significant issue in the electromagnetic industry and academia. This paper focused on a comprehensive algorithm for developing a 5G base station antenna array. The suggested algorithm aims to provide a high-gain array antenna with a continuous wide scan angle without a grating lobe, as much as a compact size, low cost, and simplicity of fabrication, especially in the array feeding network system. The best architecture is specified by comparing the array factor of numerous subarray combinations to achieve the grating lobe’s minimum level. By considering additional limitations in our approach, such as different subarray symmetric architecture, complex weighting function, minimal number of overlapped elements, and an optimal number of microstrip layers, we improve the specification over previous research and lower the runtime procedure. The proposed method is also used to construct a linear array antenna with 49 radiating elements for a 5G base station antenna operating at 28 GHz. Consequently, the number of phase shifters has been reduced by more than 53%, significantly improving over earlier efforts. Then a hybrid genetic algorithm and a particle swarm optimization technique are applied to determine the optimal values of excitation coefficients to control side lobe level(SLL) and beam scanning. The amplitude and phase step variations are calculated as 0.1 and 1°, respectively. HPBW of 2.8°, gain of 28 dB, scanning up to ± 25° in one direction, and SLL below -24 dB are the electromagnetic properties of the designed aperiodic linear array. An example of implementing the suggested method, a 16-element array with a random overlap subarray structure, including the feeding network and microstrip antenna element, will be modeled using a full-wave simulator. The simulation results show that the proposed algorithm is efficient for designing array topology.
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Pryadko, N. S., A. D. Yhnatev, H. M. Shevelova, and K. V. Ternova. "Gas mass flow control in jet equipment." Technical mechanics 2021, no. 4 (December 7, 2021): 137–49. http://dx.doi.org/10.15407/itm2021.04.137.
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Based on a numerical simulation of gas flows in an ejector unit and an analysis of grinding chamber acoustic signals, this paper shows ways to increase the efficiency of jet grinding. To prevent ejector speed-up tube wear and to obtain a ground product without impurities, the effect of feeding an additional energy carrier flow on the flow pattern in the speed-up tube of a jet mill was studied. A comparative analysis of the ejector flow pattern as a function of the presence of an additional feed and the speed-up tube shape was carried out. It was shown that the use of a conical nozzle offers a more uniform flow at the ejector outlet. The additional energy carrier feed provides a uniform increase in flow speed and reduces speed-up tube wall wear. The acoustic signals of the mill working zones were related to the jet grinding process parameters, around which a ground product quality control method was developed. The paper presents a technique for determining the material particle size in the energy carrier flow from the results of acoustic monitoring of the process. The technique uses the established relationship between the dispersion of the acoustic signal characteristic frequency and the mass of the corresponding fracture of the mixture in in-flow material transportation. The technique speeds up material particle size determination and improves the finished product quality. An automatic system was developed to control the grinding process by controlling the loading process according to the characteristics of the grinding zone acoustic signals. An operating model of a controlled hopper of a gas jet mill was made. The operability of the control system was verified on a simulation model, which includes a control objet (mill) model and a control system model. It was shown that the system of mill loading automatic control by the characteristics of the grinding zone acoustic signals offers an up to 10 percent increase in mill capacity, which was verified in industrial conditions at Vilnohorsk Mining and Metallurgical Plant.