Relevant bibliographies by topics / Polymer microbeads

Academic literature on the topic 'Polymer microbeads'

Author: Grafiati
Published: 10 December 2022
Last updated: 29 January 2023

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Journal articles on the topic "Polymer microbeads"

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Okunlola, Adenike, and Shukuralilahi Abidemi Adewusi. "Development of Theophylline Microbeads Using PregelatinizedBreadfruit Starch (Artocarpus altilis) as a Novel Co-polymer for Controlled Release." Advanced Pharmaceutical Bulletin 9, no. 1 (February 21, 2019): 93–101. http://dx.doi.org/10.15171/apb.2019.012.

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Purpose: The aim of this study was to prepare formulations of theophylline microbeads usingpregelatinized breadfruit starch (Artocarpus altilis, family Moraceae) in combination withsodium alginate and chitosan at various polymer: drug ratios. Microbead formulations forcontrolled delivery of theophylline would be better alternatives to conventional dosage formsfor optimized drug therapy.Methods: The native and pregelatinized starches were characterized for morphology (scanningelectron microscope), crystallinity (Fourier transform intra-red spectroscopy, FTIR and X-raydiffractometer, XRD), thermal flow (differential scanning colorimeter), density and flowproperties. Theophylline microbeads were prepared by ionic gelation and characterized usingsize, swelling index, entrapment efficiency and time required for 15% and 50% drug release (t15and t50 respectively).Results: FTIR and XRD spectra revealed the orderly arrangement of granules of the semi-crystallinebreadfruit starch was disrupted on gelatinization. The viscosity and flow of pregelatinized starchwere enhanced. Theophylline microbeads were near spherical in shape with size range 1.09± 0.672 to 1.58 ± 0.54 mm. FTIR and XRD spectra confirmed there was no drug-polymerinteraction. Microsphere size, swelling increased while entrapment and dissolution time (t50)reduced with polymer: drug ratio. The entrapment efficiency ranged from 30.99 ± 1.32 to 78.50± 2.37%. Optimized formulation, starch: alginate ratio 3:1 at polymer: drug ratio of 2:1, gave aprolonged dissolution time (t50 = 8.40 ± 1.20 h).Conclusion: Breadfruit starch was suitable as a copolymer for the controlled delivery oftheophylline in microbeads which could serve as a substitute to synthetic polymers in drugdelivery.
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Větvička, Václav, and Lubor Fornůsek. "Polymer microbeads in immunology." Biomaterials 8, no. 5 (September 1987): 341–45. http://dx.doi.org/10.1016/0142-9612(87)90003-2.

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Okunlola, A., and S. T. Oloye. "Influence of Pregelatinized Breadfruit Starch-Alginate Blend as a Sustained Release Polymer in Theophylline Microbeads Using Box Behnken Design." Nigerian Journal of Pharmaceutical Research 16, no. 2 (January 19, 2021): 143–51. http://dx.doi.org/10.4314/njpr.v16i2.5.

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Background: Apart from the coating property of modified starches on drugs, these natural polymers also acts as release rate retardants.Objectives: To evaluate the potential of pregelatinized breadfruit (Artocarpus altilis) starch as a carrier in microbead formulations of theophylline using different blend combinations with sodium alginate and to determine the optimized formulation using Box-Behnken design.Method: Theophylline microbeads were prepared using the ionic gelation method. The 3 factor-3 level Box-Behnken design was employed for constructing polynomial models to optimize the microbeads, involving 3 independent variables (polymer type, X1, polymer: drug ratio, X2, and concentration of calcium chloride, X3) and 2 dependent variable (entrapment efficiency and quantity of drug released in 12 h, Q12).Results: Entrapment efficiency was 35 - 71 % while the values of Q12 was 38 - 88 %. The three variables, X1, X2 and X3, were positive for entrapment efficiency but negative for Q12, implying that increase from low to medium and then to high level resulted in an increase in entrapment but a decrease in Q12 (sustained release), both desirable effects. Factor X1 had the most significant influence on entrapment efficiency and Q12 (p = 0.002; p = 0.0001, respectively). The optimized formulation with starch:polymer 2:1, polymer:drug 3:1 and 7.5%w/v calcium chloride solution gave an entrapment efficiency 65% with Q12 of 38.75%.Conclusion: Pregelatinized breadfruit starch enhanced entrapment efficiency while retarding drug release, showing its potential as a polymer for sustained release in microbead formulations. Keywords: Box-Behnken design; Breadfruit starch; Ionic gelation, Microbeads, Pregelatinization
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Debasis Nayak and Saravanan Kaliyaperumal. "Development and effect of drug release from simvastatin loaded sodium alginate micro beads." World Journal of Biology Pharmacy and Health Sciences 12, no. 3 (December 30, 2022): 348–58. http://dx.doi.org/10.30574/wjbphs.2022.12.3.0259.

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The objective of the present study was to prepare the microbeads of Simvastatin loaded with sodium alginate to provide control release of drug delivery system. So, the design of drug delivery system was to improve and enhance the bioavailability of drug. The Simvastatin loaded microbeads were prepared by the ionic gelation method using polymer such as sodium alginate as a natural substance. Simvastatin loaded sodium alginate microbeads were formulated by different cross linking agent like CaCl₂, BaCl₂, ZnCl₂ and FeCl₃ in different ratio. The microbeads were spherical, free flowing exhibited drug content uniformity and high drug encapsulation efficiency. The swelling and drug release behavior depends upon amount of cross linking agent used in the microbeads. This released the drug up to 24 hours where beads released the drug up to 6 hours. The FTIR analysis of drug, polymers and the optimized formulation indicated the compatibility of the drug with the polymers. The DSC studies confirmed the drug polymer interaction in the microspheres. The SEM studies influence the rate of drug release from the microbeads. The present study concludes that the swelling and In-vitro release behavior of Simvastatin loaded sodium alginate microbeads can be considered as a promising control release drug delivery system.
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Nedovic, Viktor, Verica Manojlovic, Ulf Pruesse, Branko Bugarski, Jasna Djonlagic, and Klaus Vorlop. "Optimization of the electrostatic droplet generation process for controlled microbead production: Single nozzle system." Chemical Industry and Chemical Engineering Quarterly 12, no. 1 (2006): 53–57. http://dx.doi.org/10.2298/ciceq0601053n.

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The aim of this study was to optimize the electrostatic extrusion process for producing small, spherical and uniform microbeads with different fluid viscosities by varying the operating parameters in very wide ranges. Alginate was used as a model polymer. Since the rheological behavior of the solution is one of the parameters that affects the flow dynamics during extrusion, viscosity measurements of solutions with different alginate content were performed. The results obtained in this study show that an electrostatic droplet generator can be used for the production of spherical microbeads of narrow size distribution from low- and medium- viscous fluids (0.5, 1, and 2% of alginate). The average microbead diameter for low-viscous solutions was less than 100 micrometers. It was possible to obtain beads smaller than 500 micrometers that were very uniform (standard deviations less than 2.5%) and of spherical (the shape distortion was less than 1%) from medium-viscous alginate solution (2%). By reducing the polymer flowrate to less than 1 ml/h, even smaller microbeads were produced with diameters of about 300 micrometers. The particular contribution of this paper is in exceeding limitations regarding the use of high-viscous polymer solutions. Optimization of the operating conditions that included the use of a very small needle (0.15 mm), enlargement of the electrode distance to more than 20 cm and a severe reduction in the polymer flow rate to lower than 5 ml/h (for 3% alginate) or 1 ml/h (for 4% alginate) enabled the production of small, entirely spherical and uniform microbeads with an average microbead diameter lower than 500 and 700 micrometers in the case of 3 and 4% of alginate, respectively.
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Ren, Zhi Min, Xi Nie, and Sheng Shu Ai. "Influence of Blocking Agents on Non-Specific Background of Polystyrene Microbeads in Serum Immunoassay." Advanced Materials Research 641-642 (January 2013): 858–61. http://dx.doi.org/10.4028/www.scientific.net/amr.641-642.858.

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In this paper, we used bovine serum albumin and polymer as the blocking agents and investigated the effect of blocking agents on non-specific background of polystyrene microbead that used the human serum immunoassay.The results showed that the nonspecific background is lower by using polymer blocking agents. The best blocking condition was that microbeads were blocked by PVXT (0.5% polyvinyl alcohol PVA, 0.8% polyvinylpyrrolidone, 0.05% Tween-20, PBS phosphate buffer, pH7.0) for two hours at room temperature.
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Foti, Leonardo, Andre Sionek, Elis Moura Stori, Paula Poli Soares, Miriam Marzall Pereira, Marco Aurélio Krieger, Cesar Liberato Petzhold, et al. "Electrospray induced surface activation of polystyrene microbeads for diagnostic applications." Journal of Materials Chemistry B 3, no. 13 (2015): 2725–31. http://dx.doi.org/10.1039/c4tb01884b.

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Proposed electrochemical reaction mechanism: (a) highly charged microbeads approach the electrolyte; (b) microbeads sink and are solvated by water molecules; (c) water oxidation reaction disrupts PS surface bonds; (d) oxygen is incorporated into the polymer chains.
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Dahima, Rashmi. "Formulation and Evaluation of Pseudoephedrine Hydrochloride Loaded Alginate Microbeads." Journal of Drug Delivery and Therapeutics 10, no. 3 (May 15, 2020): 137–41. http://dx.doi.org/10.22270/jddt.v10i3.4094.

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Multiple unit dosage forms such as microbeads have increased acceptance because of added even spreading of the drug in the gastrointestinal tract, unvarying drug absorption, abridged local irritation and removal of undesirable intestinal retaining of polymeric material, when compared to non-disintegrating single unit dosage form. The purpose of the presented research is to develop microbeads of pseudoephedrine hydrochloride utilizing sodium alginate as the hydrophilic carrier in combination with HPMC as drug release modifier to lessen the dosing frequency and thereby advance the patient compliance. The microbeads were formulated by varying concentrations of HPMC and calcium chloride. The optimum formulation was chosen based upon in vitro drug release studies and further evaluated. The compatibility of drug-polymer was studied using FTIR analysis. The prepared formulation underwent evaluation for various parameters like drug entrapment, microbeads size, swelling index, mucoadhesive property and stability. No significant drug-polymer interactions were observed in compatibility studies and the formulation was found to be stable on 45 days storage. The formulations exhibited an extended drug release pattern which was the ultimate aim of the study. The microbeads represented good yield, high drug entrapment, low microbeads size and appropriate swelling property. The in vitro wash-off test indicated that the sodium alginate microbeads represent decent mucoadhesive properties. Henceforth, the formulated HPMC coated sodium alginate beads can be utilized as a substitute and cost-effective carrier for the oral controlled delivery of pseudoephedrine hydrochloride. Keywords: microbeads, pseudoephedrine hydrochloride, sodium alginate, drug release
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Kage, Daniel, Linn Fischer, Katrin Hoffmann, Thomas Thiele, Uwe Schedler, and Ute Resch-Genger. "Close Spectroscopic Look at Dye-Stained Polymer Microbeads." Journal of Physical Chemistry C 122, no. 24 (June 8, 2018): 12782–91. http://dx.doi.org/10.1021/acs.jpcc.8b02546.

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Liu, Yixi, Le Liu, Yonghong He, Qinghua He, and Hui Ma. "Quantum-dots-encoded-microbeads based molecularly imprinted polymer." Biosensors and Bioelectronics 77 (March 2016): 886–93. http://dx.doi.org/10.1016/j.bios.2015.10.024.

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Dissertations / Theses on the topic "Polymer microbeads"

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Kage, Daniel. "Studies on fluorophore-loaded polymer microbeads and luminescence lifetime encoding in flow cytometry." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20608.

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Die Dissertation umfasst zwei Themenblöcke: Zum einen wurden die optisch-spektroskopischen Eigenschaften von fluoreszenten, farbstoffbeladenen Polymer-Mikropartikeln untersucht. Zum anderen wurde die Anwendbarkeit solcher Partikel für die Lumineszenzlebensdauer-Kodierung in der Durchflusszytometrie evaluiert. Die Charakterisierung der farbstoffbeladenen Mikropartikel erfolgte mittels optischer Spektroskopie. Am Beispiel mit Rhodamin 6G beladener Polymethylmethacrylat-Partikel konnte ein besseres Verständnis des Einbaus der Farbstoffmoleküle und der resultierenden Fluoreszenz-Charakteristika gewonnen werden. Es stellte sich heraus, dass die Beladungseffizienz stark vom mittleren Partikeldurchmesser und den Synthesebedingungen abhängt. In Verbindung mit den beobachteten optisch-spektroskopischen Eigenschaften wurde geschlussfolgert, dass sich eine farbstoffreiche Schicht an der Oberfläche der Partikel bildet, die sich wesentlich von den sterisch eingebauten Farbstoffmoleküle im Partikelvolumen unterscheidet. Hohe Farbstoffkonzentrationen in dieser Oberflächenschicht führen vermutlich zu Aggregation. Des Weiteren deuten Veränderungen der Fluoreszenzeigenschaften auf intrapartikuläre Energiewanderung bei zunehmender Farbstoffkonzentration hin. Diese Interpretation der experimentellen Ergebnisse konnte qualitativ durch einen Algorithmus zur Simulation der Energiewanderung bestätigt werden. Die Anwendbarkeit der Lumineszenzlebensdauer als Kodierungsparameter in der Zeitdomäne konnte unter Verwendung eines Durchflusszytometer-Prototypen analysiert werden. Die wohl größte Herausforderung bei der Lebensdauermessung in der Durchflusszytometrie ist die kurze Interaktionszeit zwischen Objekt und Anregungslicht. Synthetische Daten wurden herangezogen, um den Einfluss einzelner Messparameter und -bedingungen unabhängig voneinander abzuschätzen. Es konnte festgestellt werden, dass die Lumineszenzlebensdauer als Kodierungsparameter in der Zeitdomäne prinzipiell zugänglich ist.
This thesis comprises two main topics. First, the optical-spectroscopic properties of fluorescent microbeads loaded with organic dyes were studied. In the second part, the feasibility of time-domain luminescence lifetime encoding in flow cytometry based on such microbeads was assessed. The study of the dye-loaded polymer microbeads was based on optical spectroscopy. Poly(methyl methacrylate) beads loaded with rhodamine 6G were used as an example system to achieve a better understanding of the dye incorporation procedure. The dye loading efficiency turned out to be strongly dependent on the mean diameter of the beads and on the amounts of certain compounds used for the bead synthesis. In correlation with the observed fluorescence characteristics, it was deduced that a layer with high local dye concentration forms around each bead. The properties of this layer substantially differ from those of the sterically incorporated dye molecules in the bead core. The high dye concentration in this layer results in aggregation accompanied by the respective changes of the fluorescence characteristics of the beads. Moreover, the observed changes in fluorescence properties indicated the existence of an intra-particulate energy migration process at increased dye loading concentrations. A simulation of the energy migration process based on a random walk algorithm confirmed the interpretation of the experimental results. For the assessment of luminescence lifetime encoding in time-domain flow cytometry, a prototype setup was used. The main issue of lifetime determination in flow cytometry is represented by the short interaction time of only tens of microseconds of the objects with the excitation light spot. Synthetic data were used to study certain measurement parameters and conditions as well as the data analysis procedure independently of other influences. As a result, luminescence lifetime is generally applicable as an encoding parameter in time-domain flow cytometry.
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Kage, Daniel [Verfasser], Stefan [Gutachter] Kirstein, Oliver [Gutachter] Benson, and Michael [Gutachter] Kumke. "Studies on fluorophore-loaded polymer microbeads and luminescence lifetime encoding in flow cytometry / Daniel Kage ; Gutachter: Stefan Kirstein, Oliver Benson, Michael Kumke." Berlin : Humboldt-Universität zu Berlin, 2019. http://d-nb.info/1198207000/34.

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Khan, Ikram Ullah. "Microfluidic-assisted synthesis and release properties of multi-domain polymer microparticles drug carriers." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAF042/document.

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Les caractéristiques et les propriétés de libération de microparticules chargées de médicament dépendent de la nature des matériaux employés, des propriétés physicochimiques des microparticules, du choix de la méthode de production, et enfin des propriétés des molécules encapsulées. A l'inverse de la plupart des méthodes conventionnelles, les méthodes microfluidiques présentent l’avantage de bien mieux contrôler la génération de gouttelettes, leur taille et leur distribution de tailles. Ainsi des dispositifs microfluidiques à base de capillaires ont été développés pour obtenir des microbilles de polymère mais également des microparticules de type janus, coeur-écorce ou troyenne, toutes monodisperses en taille et chargées de médicament(s). Ces particules ont été produites à partir de solutions de monomère qui furent polymérisées par irradiations UV de telle sorte à garder intacte l'activité des molécules chargées. Ces dispositifs peuvent être assemblés dans un court laps de temps et un simple changement dans leur conception permet d’obtenir des morphologies de particules très différentes. Ces particules ont été développées dans le but de résoudre les problèmes rencontrés dans l’administration orale de médicaments. Par exemple les microbilles peuvent être utilisées pour délivrer des anti-inflammatoires non stéroïdiens de manière continue tandis que les particules Janus peuvent libérer, simultanément et sur le même site, deux principes actifs possédant des propriétés complètement différentes (solubilité, compatibilité) également de manière prolongée. Quant aux particules coeur-écorce, elles ont été conçues pour cibler la région du côlon de l'intestin humain, et y libérer simultanément deux médicaments. Les particules troyennes furent synthétisées à l’aide d’un procédé microfluidique semi-continu qui a permis une manipulation plus sécurisée des nanoparticules vectrices ainsi que la libération continue d’un médicament dans un liquide gastrique simulé. Chaque système a été entièrement caractérisé pour assurer l’invariance entre lots et la reproductibilité. En général, la libération des ingrédients actifs a pu être facilement contrôlée/ajustée par le réglage des paramètres opératoires et de matériaux tels que les débits des différentes phases, la nature et la concentration du médicament, des (co)monomères, des agents tensioactif et de réticulation, le pH du milieu de libération. Ces différents paramètres influencent les propriétés des microparticules telles que leur morphologie, forme, taille et densité de réticulation du réseau polymère
Characteristics and release properties of drug loaded microparticles depend upon material used and choice of production method. Conversely to most of the conventional ones, microfluidic methods give an edge by improving the control over droplet generation, size and size distribution. Capillary-based microfluidic devices were successfully used to obtain monodisperse drug(s) loaded microbeads, janus, core-shell and trojan particles using UV initiated free radical polymerization while keeping activity of active loaded molecules. These devices can be assembled in a short period of time and a slight change in design gives completely different microparticles morphologies. These particles were developed with the aim to address different issues experienced in oral drug delivery. For instance microbeads can be used to deliver NASIDs in a sustained release manner while janus particles can release two APIs with completely different properties (solubility, compatibility) also in a sustained release manner. Core-shell particles were designed to target colonic region of human intestine for dual drug delivery. Trojan particles were synthesized in a new semi-continuous microfluidic process, thus improving nanoparticles safety handling and release in simulated gastric fluid. Each system was fully characterized to insure batch to batch consistency and reproducibility. In general, the release of active ingredients was controlled by tuning the operating and material parameters like phases flow rates, nature and concentration of drug, (co)monomers, surfactant and crosslinker, pH of release media with the result of different particle morphologies, sizes and shapes or matrix crosslinking density
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Wong, Christopher James, and chrisjwong@yahoo com au. "High Resolution Polymer Gel Dosimetry for Small and Micro Field Dosimetry, and Development of Innovative Polymer Gel Dosimeters." RMIT University. Medical Sciences, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091002.161512.

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Current radiotherapy techniques are focused on delivering effective treatments while sparing surrounding healthy tissues. As a result, radiotherapy treatments are using narrower and more tightly conforming therapy techniques. For these treatments to be effective an accurate measure of the dose delivered by these very narrow radiotherapy beams, both in and around the target volume, is required. It is a challenging task for the conventional type dosimeters to determine dose distribution in such small fields. The best example of such fields is microbeam beam radiotherapy (MRT), a developing treatment technique that takes this requirement even further. MRT delivers an array of micrometre size radiotherapy beams to the target. MRT has been shown to be highly effective, but reliable dosimetry of MRT is challenging due to the micrometre scales involved. Attempts to determine the MRT dose distribution have been documented for using special type dosimeters such as radioch romic film and MOSFET detectors, as well as Monte Carlo simulations. This thesis investigates polymer gels as a dosimeter for dose distribution measurements of small radiotherapy fields and microbeams. Polymer gel dosimetry is a technique which uses a tissue-equivalent gel to act as both a three-dimensional dosimeter and a phantom at the same time. These gels polymerise when exposed to ionising radiation and the response is locally dose dependent linearly. This thesis investigates the use of polymer gels for the dosimetry of small sub-centimetre (down to 3 × 3 mm2) and micrometre radiotherapy fields. A high resolution imaging technique is also required for such small beam dosimetry. This work used special high strength MRI scanners to analyse polymer gels at high resolution. This work explores the feasibility of polymer gels irradiated by microbeams and analysed using Raman spectroscopy as a dosimeter for synchrotron generated microbeams. MRT is characterised by very high doses, and special high-dose resistive types of gel were developed as part of this work. It is shown that polymer gels imagined using Raman spectroscopy techniques are capable of measuring the dose distribution of microbeam radiation techniques. This thesis also investigates the use of polymer gels to measure dose perturbations caused by metallic artefacts. Metallic artefacts, such as a surgical aneurysm clip, can be left in a patient and cause dose perturbations during radiotherapy procedures. Polymer gels were used to determine the degree of dose enhancement induced by an aneurysm clip placed inside when irradiated with a typical stereotactic radiotherapy procedure. In addition, this thesis used gels in several other innovative applications. Photonuclear interactions generated in gel by high energy x-ray beams were measured via secondary neutrons. Special clear-type gels that do not change colour with irradiation were developed. Polymer gels were investigated for dosimetry of an extremely high dose rate capacitor type linear accelerator. And polymer gels were for measurement of a high energy proton beam.
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Wu, Mei. "Polymer microarrays for microbial high-content screening." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7664.

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Research on the interactions between microbes and polymeric materials constitutes an important part in antimicrobial identification and provides an insight into microbial response on the polymer surfaces. Herein, a high-content screening method with polymer microarray technology was developed to investigate microbe-polymer interactions, especially in studying adhesion/repellence of microbes (bacteria and parasites). Firstly, the polymer microarray approach was used to successfully identify polymers which either selectively captured or prevented the binding of major food-borne pathogen, Salmonella Typhimurium. A parallel study with a lab strain of Escherichia coli was also carried out, revealing polymers which either displayed a common binding activity or which exhibited species discrimination. Likewise, this polymer microarray technology was applied to more bacterial strains, such as Campylobacter, Clostridium, Streptococcus, Klebsiella and their cocktails to discover families of substrates that displayed strong broad-spectrum bacterial non-binding activity. These synthetic polymers represented a novel class of coating materials which can be used to prevent surface colonisation and subsequent formation of bacterial biofilms. The study of protozoan-polymer interactions was also explored in this thesis. Polymers were identified which either bound or prevented parasites (Crysporidium parvum and Giardia lamblia) binding. Material properties, including wettability, surface roughness and polymer composition were analysed to study correlation of parasite binding and the generation of polymer structure function relationships.
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Drew, D. W. "A novel MeV ion microbeam technique for measuring diffusion of small molecules in polymeric & biological matrices." Thesis, University of Surrey, 1996. http://epubs.surrey.ac.uk/843536/.

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This thesis describes initially the development of novel MeV ion micro-beam techniques. It then discusses their application to the measurement of the diffusion of small molecules in polymeric and biological matrices which hitherto were not possible. The matrices studied were skin tissue, human hair, polymeric cable insulation and hydrophilic polymers. The important novel aspects of the techniques are: Use of 3He scanning ion microbeam. Use of dual uncollimated charged particle detectors to measure induced nuclear reaction products. Use of a very thin window detector capable of detecting X-rays from elements heavier than beryllium. Fast freezing of samples with liquid nitrogen to freeze diffusion profiles and eliminate sample deformation. Use of a liquid nitrogen cooled target stage to both retain water and effectively eliminate beam heating effects when exposing samples to vacuum and the ion microbeam respectively.
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Zethof, Jeroen H. T. [Verfasser], Karsten [Gutachter] Kalbitz, Karsten [Akademischer Betreuer] Kalbitz, Georg [Gutachter] Guggenberger, and M. Estela [Gutachter] Nadal-Romero. "The role of extracellular polymeric substances from microbes in soil aggregate stabilization in semiarid grasslands / Jeroen H.T. Zethof ; Gutachter: Karsten Kalbitz, Georg Guggenberger, M. Estela Nadal-Romero ; Betreuer: Karsten Kalbitz." Dresden : Technische Universität Dresden, 2021. http://d-nb.info/1237320054/34.

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Souza, Cláudia Telles de. "Microestruturação de membranas de poli (tereftalato de etileno) por microfeixe de íons." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/83679.

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Neste trabalho, o processo de estruturação por microfeixe de íons foi utilizado para a produção de membranas microporosas em folhas comerciais de PET. O processo de estruturação por microfeixe de íons consiste basicamente na interação direta entre um feixe de íons de dimensões micrométricas com o material em questão. As zonas modificadas pelo feixe são removidas do restante do material através de um processo químico. Nesse contexto, durante o desenvolvimento deste trabalho, sistemáticas experimentais para o processo de estruturação foram desenvolvidas. Com o intuito de operacionalizar a linha de microfeixe presente no Laboratório de Implantação Iônica da UFRGS, foi necessário realizar um estudo aprofundado sobre o funcionamento de todo o sistema, verificando problemas e explorando a potencialidade de técnicas não convencionais de análise de materiais. O estudo sobre a sistemática de estruturação ocorreu através da investigação de parâmetros clássicos, como fluência utilizada durante a irradiação e tempo de ataque químico. Para atingir tais objetivos, amostras de poli (tereftalato de etileno) (Mylar) de 12 μm foram irradiadas com microfeixe de íons (H+ e He++) com energias de 3 e 2,2 MeV e fluências que variaram entre 1 x 1011 e 6 x 1015 íons/cm2. Posteriormente à irradiação, as amostras foram submetidas a um ataque químico com solução alcalina de hidróxido de sódio 6 M durante tempos que variaram de 0,5 à 60 minutos. A temperatura do ataque em todos os casos se manteve fixa em 60°C. A caracterização das amostras foi realizada através de microscopia eletrônica de varredura (MEV) e por microscopia de transmissão iônica (STIM). As amostras também foram caracterizadas através de medidas elétricas utilizando um circuito de corrente alternada. O processo de enxertia (grafting) foi testado nas membranas estruturadas, utilizando um hidrogel de PNIPAAm com concentrações de 0,340, 0,450 e 0,700 g/L. Tais resultados também foram analisados através de MEV. O estudo sobre a linha de microfeixe permitiu verificar a existência de problemas relacionados ao registro da carga elétrica durante as irradiações. Além disso, para o ajuste do foco do feixe de íons, foram feitas curvas de calibração de corrente para as lentes magnéticas considerando diferentes energias de feixe. O processo de estruturação através da técnica de microfeixe de íons se mostrou eficaz para a produção de estruturas regulares e definidas em folhas de PET. A fluência ótima de prótons a ser utilizada nos processos de estruturação foi estimada em 6 x 1014 íons/cm2. Para esta fluência, tempos de ataque químico inferiores a 1 minuto já são suficientes para corroer toda a parte irradiada. Entretanto, tempos um pouco mais longos (e.g. 2 minutos) tornam o processo mais reprodutível. Com relação à geometria das estruturas fabricadas, observou-se irregularidades em estruturas que, em princípio, deveriam ser simétricas. Esse problema foi atribuído à assimetria do feixe, proveniente de ajustes dos parâmetros de colimação do feixe. Finalmente, o estudo do processo de enxertia mostrou que o hidrogel adere nas paredes das estruturas, porém não as preenche. Para concentrações elevadas (e.g. 0,7 g/L) o processo não é tão eficiente, sendo que não é verificada a redução da área das microestruturas pela inserção do hidrogel. As medidas elétricas mostraram a existência de regimes distintos e dependentes da frequência da corrente alternada. Os polímeros apresentaram basicamente comportamentos resistivo e capacitivo.
In this work, the process of irradiation of PET foils with ion beams in the micrometer size range was used for the production of microporous membranes. Basically, this process consists on the direct interaction between the ion beam and the material under study. The regions modified by the beam are removed from the material through a chemical process. In this context, experimental procedures for the production process of the membranes were developed during the course of this work. In order to make the microbeam station of the Ion Implantation Laboratory of the Federal University of Rio Grande do Sul (UFRGS), it was necessary to perform a thorough study of the operational parameters of the system, thus allowing a proper identification of problems and providing grounds for pushing the technique to the frontier of materials science. To achieve such objectives, foils of polyethylene terephtalate (Mylar®) 12 μm thick were irradiated with H+ and He++ ions with 3 e 2,2 MeV respectively. Fluencies varied from 1 x 1011 and 6 x 1015 ions/cm2. After the irradiation, the foils were submitted to an etching procedure using alkaline solution of sodium hydroxide at 6 M during periods of time varying from 0,5 to 60 minutes. In all cases, the temperature of the etching was fixed at 60°C. The characterization of the samples was performed through scanning electron microscopy (SEM) and scanning transmission ion microscopy (STIM). The samples also were characterized by electric measurements using an AC current circuit. The process of grafting was tested on the structured membranes using a PNIPAAm hydrogel with concentrations of 0,340, 0,450 and 0,700 g/L. The results of this study were also analyzed through MEV. With the present study, it was possible to pinpoint problems related to the integration and recording of the charge during the irradiations. Besides that, calibration curves were obtained relating the electric currents needed on the magnetic lenses for an optimal ion beam focus and the beam energy. The irradiation process with ion beam proved itself efficient for the production of regular patterns on PET foils. The optimum dose of prótons to be used on the patterning processes was estimated in 6 x 1014 ions/cm2. For this dose, etching times smaller than 1 minute were enough to remove all the irradiated area. However, times slightly longer (e.g. 2 minutes) make the process more reproducible. Regarding the geometry of the patterns generated by the ion irradiation, asymmetries were observed on structures that were supposed to be symmetric. This problem was attributed to the asymmetry of the beam spot on the target due to the settings of the objective slits that collimates the beam. The study of the grafting process showed that the hydrogel adheres to the structures walls, but does not fill it. For high concentrations (e.g. 0,7 g/L), the process is not efficient, since no reduction of the area of the microstructures by the insertion of the hydrogel was observed. The electric measurements showed the existence of distinct regimes as a function of the frequency of the alternate current. Basically, the polymer foils present resistive and capacitive behaviors.
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Liong, Rolan Yuk Loong. "BACTERIAL GROWTH ON METAL AND NON-METAL SURFACES IN A STATIC BIOREACTOR." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/923.

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Research was conducted to observe bacterial growth on the surface of metals in a static bioreactor. Metal and non-metal samples were subjected to bacterial exposure (1 day and 9 days). The metal samples were surface treated prior to bacterial exposure. The microstructures of the surface treated samples were analyzed by optical microscopy. After exposure, the microstructures of the samples were analyzed by scanning electron microscopy (SEM). The analysis suggested that microbial attachment on the surface was related to the underlying microstructure of steel. The preferential attachment of microbes could potentially be influenced by cathodic and anodic regions created by the electrolytic cells.
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Lewis, Patrick C. "Polymer microbeads for optical and biological applications." 2004. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=81186&T=F.

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Books on the topic "Polymer microbeads"

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Lewis, Patrick C. Polymer microbeads for optical and biological applications. 2004.

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Mobley, David P. Plastics from Microbes: Microbial Synthesis of Polymers and Polymer Precursors. Hanser Gardner Publications, 1994.

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P, Mobley David, ed. Plastics from microbes: Microbial synthesis of polymers and polymer precursors. Munich: Hanser Publishers, 1994.

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Kirchman, David L. Elements, biochemicals, and structures of microbes. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198789406.003.0002.

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Microbiologists focus on the basic biochemical make-up of microbes, such as relative amounts of protein, RNA, and DNA in cells, while ecologists and biogeochemists use elemental ratios, most notably, the ratio of carbon to nitrogen (C:N), to explore biogeochemical processes and to connect up the carbon cycle with the cycle of other elements. Microbial ecologists make use of both types of data and approaches. This chapter combines both and reviews all things, from elements to macromolecular structures, that make up bacteria and other microbes. The most commonly used elemental ratio was discovered by Alfred Redfield who concluded that microbes have a huge impact on the chemistry of the oceans because of the similarity in nitrogen-to-phosphorus ratios for organisms and nitrate-to-phosphate ratios in the deep oceans. Although statistically different, the C:N ratios in soil microbes are remarkably similar to the ratios of aquatic microbes. The chapter moves on to discussing the macromolecular composition of bacteria and other microbes. This composition gives insights into the growth state of microbes in nature. Geochemists use specific compounds, “biomarkers”, to trace sources of organic material in ecosystems. The last section of the chapter is a review of extracellular polymers, pili, and flagella, which serve a variety of functions, from propelling microbes around to keeping them stuck in one place.
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W, Drew D. A novel MeV ion microbeam technique for measuring diffusion of small molecules in polymeric & biological matrices. 1996.

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Book chapters on the topic "Polymer microbeads"

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Jang, Yeonggul, Byunghwan Jeon, and Yoojin Chung. "Core-Shell Detection in Images of Polymer Microbeads." In Communications in Computer and Information Science, 9–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-35521-9_2.

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Fang, Cheng, and Youhong Tang. "Polymer Microbead-Templated Nanostructures." In Polymer-Engineered Nanostructures for Advanced Energy Applications, 31–50. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-57003-7_2.

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Crescenzi, V., and M. Dentini. "Microbes in Polymer Chemistry." In ACS Symposium Series, 221–32. Washington, DC: American Chemical Society, 1996. http://dx.doi.org/10.1021/bk-1996-0627.ch018.

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Koestler, Robert J. "Polymers and Resins as Food for Microbes." In Of Microbes and Art, 153–67. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/978-1-4615-4239-1_11.

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Singh, Purnima, Vibha Pandey, and Prerana Parihar. "Microbes Derived Exopolysaccharides Play Role in Salt Stress Alleviation in Plants." In Microbial Polymers, 355–72. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0045-6_16.

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Kendall, William F., and Emmanuel C. Opara. "Polymeric Materials for Perm-Selective Coating of Alginate Microbeads." In Cell Microencapsulation, 95–109. New York, NY: Springer New York, 2016. http://dx.doi.org/10.1007/978-1-4939-6364-5_7.

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Rasu, Kulanthaisamy Mohan, and Alagarsamy Arun. "Exploring biodegradable polymer production from marine microbes." In Biodegradable Polymers: Recent Developments and New Perspectives, 33–64. IAPC Publishing, 2017. http://dx.doi.org/10.5599/obp.14.7.

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Kumar, Amrendra, and Swati Agarwal. "Microbial Products and Their Role in Soil Health and Sustainable Agriculture." In Advances in Environmental Engineering and Green Technologies, 181–204. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-7062-3.ch007.

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Microbial products are being used from ages in known as well as unknown forms. Some common products harvested from microbes include proteins, amino acids, antibiotics, antibodies, secondary metabolites, organic acids, lipids, and so on. It also includes antivirals, polymers, surfactants, enzyme inhibitors, nutraceuticals, and many industrial and agricultural products. Moreover, sometimes the whole single celled microbes are harvested as a rich source of protein called single cell proteins. In a nutshell, all these products cover almost every economic sector like food, feed, agriculture, healthcare, fuel, textile, and pharmaceutical. Hence, these microbial products have serious socio-economic impressions and have unleashed enormous possibilities in terms of commercial production. However, only a small fraction of microbial products are exploited, and a larger chest remains to be achieved. In the chapter, the importance of microbes in the production of proteins, enzymes, and secondary metabolites are discussed in detail with special emphasis on sustainable agriculture.
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Gross, Richard A., and Shekar Mekala. "Microbial and Enzymatic Synthesis of Polymers." In Lipid Modification by Enzymes and Engineered Microbes, 239–56. Elsevier, 2018. http://dx.doi.org/10.1016/b978-0-12-813167-1.00011-6.

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Yogesh, B. J., and S. Bharathi. "Industrial Aspects of Microbes." In Industrial Applications of Soil Microbes, 59–76. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815039955122010007.

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This chapter deals with the significance of soil microbes from an industrial perspective. Soil microbes are the most diverse populations to exist on earth, and they are known to have played a prominent role in the development of soil chemistry, soil texture, and soil suitability to sustain plant life. The chapter deals with the significance of cultural techniques for the isolation of desired microbial strains from the soil. The importance of screening techniques for isolates is emphasized, wherein the potential strains are tested for their physiological characteristics that are industrially beneficial. A few criteria are mentioned for judging the soil isolate’s capability to become an industrial strain. The difference between natural isolates and potential industrial strains is discussed. Useful strains are categorized based on their ability to produce primary and secondary metabolites with commercial applications in terms of economic, agricultural, and environmental significance. Industrially important microbes are listed with emphasis on the types of metabolites they produce and their applications. Knowledge of metabolic pathways involved in metabolite production and their regulation in terms of various feedback control systems are discussed. Strain improvement and its role in improving industrial aspects of microbes are highlighted. Bacillus sp. are given their due importance as the most diverse and dynamic forms of bacteria, contributing immensely to our knowledge and being the most beneficial forms of soil microbes. A few metabolites are discussed in detail, with emphasis given to enzymes, microbial polymers, amino acids, solvents, organic acids, and antibiotics. Microbial bioleaching mostly employs bacteria that could help in the recovery of metals from low-grade ores, and industries based on biomining have shown a renewed interest in this economically viable process.
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Conference papers on the topic "Polymer microbeads"

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Kingsley, David M., Andrew D. Dias, Douglas B. Chrisey, and David T. Corr. "A Novel, Laser-Based Technique to Fabricate and Precisely Pattern Cell-Encapsulated Alginate Microbeads." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14658.

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Microbeads are three-dimensional, generally spherical microstructures that are currently being investigated for applications in tissue engineering and for delivery of drugs, proteins, and DNA [1, 2]. Current microbead fabrication devices such as electrostatic bead generators, microfluidic devices, and micro-vibrators, function by using cross-linkable polymers into a crosslinking solution, such as calcium chloride in the case of alginate. These procedures allow for the controlled manipulation of microbead size, e.g., increasing electric field voltage for the electrostatic bead generator during polymer extrusion. Popular devices such as electrostatic bead generators are limited to polyelectrolyte materials because of the electric field extrusion method [3]. In addition, despite their ability to create monodispersed beads of different size, none of these technologies can precisely control microbead placement.
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Soon, Chin Fhong, Soon Chuan Wong, Wai Yean Leong, Mohd Khairul Ahamd, and Kian Sek Tee. "A flicking method for generation of polymer microbeads." In 14th International Conference on Global Research and Education, Inter-Academia 2015. Japan Society of Applied Physics, 2016. http://dx.doi.org/10.7567/jjapcp.4.011110.

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OMEROGLU, Sevde, Rahmetullah VAROL, Zeynep KARAVELIOGLU, Aslihan KARADAG, Yasemin BASBINAR, Muhammed Enes ORUC, and Huseyin UVET. "Determination of Cell Stiffness Using Polymer Microbeads as Reference." In 2020 Medical Technologies Congress (TIPTEKNO). IEEE, 2020. http://dx.doi.org/10.1109/tiptekno50054.2020.9299227.

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Lee, Doh-Hyoung, Jonghyun Oh, Robert Hart, Bakhtier Farouk, and Hongseok Moses Noh. "A Study of AC Electrokinetic Phenomena Under DC Electroosmotic Flows." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68969.

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AC electrokinetic phenomena have drawn much attention in the microfluidics and lab-on-a-chip communities since these techniques have a great potential for effective manipulation of small particles (micro- to nanoscale particles, polymer beads to biological cells and molecules) and fluids in microchannel environments. One unanswered question is how the AC electrokinetic phenomena are affected by DC electroosmotic flows that are often employed in lab-on-a-chip systems as a pumping method. This paper presents experimental and numerical studies on the interaction between AC electrokinetic phenomena and DC electroosmotic flows. The motions of polystyrene microbeads suspended in deionized water in a microchannel were studied as the main AC and DC electrokinetics parameters were varied. Numerical simulations of flow field were performed using COMSOL Multiphysics software. The forces considered in the numerical simulation include electrophoresis, DC electroosmosis, dielectrophoresis, AC electroosmosis, electrothermal effect, diffusion, Stokes drag force, and gravity. The numerical simulation results showed good agreements with experimental data. We believe that this study will contribute to the understanding of the interactions between DC and AC electrokinetic phenomena and thus enable researchers to develop powerful microdevices based on the combination of these two techniques.
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Schmid, S., P. Wagli, and C. Hierold. "Biosensor based on All-Polymer Resonant Microbeams." In 2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems (MEMS). IEEE, 2009. http://dx.doi.org/10.1109/memsys.2009.4805378.

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Bharadwaj, R. "Technological Advances in Water-less Fracking: A Case Study." In Indonesian Petroleum Association 44th Annual Convention and Exhibition. Indonesian Petroleum Association, 2021. http://dx.doi.org/10.29118/ipa21-se-169.

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Hydrofracking transfigured the concept of producing from unconventional reservoirs. The Fracking fluid used in fracturing has unlocked many tight reservoirs but in terms of an aquifer, it poses threats like consumption of large quantity of water and also, used water becomes polluted as well as recycling cost is uneconomic. This paper evaluates alternatives to water-based frac fluids and discusses their environmental & economic impact along with resource availability and commercial feasibility. Pure Propane Fracturing uses propane in combination with non-toxic man-made proppants (light glass & carbon fullerene microbeads) with desired properties. Pure Propane is fluorinated and carbonated without water or harmful additives, thereby eliminates the risk of catching fire. Pure Propane Fracturing eliminates the need for water completely and thus, a perfect option for fracturing in water scarcity regions. Fracture flow capacity of Pure Propane can be enhanced with the use of phase change chemical proppants in the slurry stage. CO2 Foam Fracturing predominantly comprises liquid carbon-dioxide which reduces the water requirement up to 80%. CO2 foam-based frac fluid uses relatively fewer chemical additives as compared to the water-based frac fluid which in-turn does minimal formation damage. Foam Fracturing fluids have high fluid recovery and clean-up efficiency. CO2 foam-based frac fluid is available in a wide range of viscosities and can also work in high pressure high temperature conditions at significantly low polymer loadings. Energized frac fluid comprises N2/CO2 (20-30%) which reduces water consumption and provides additional energy to aid in load recovery during the post-frac flow-back stage. N2 gas can propagate more easily into small pores and micro-fractures to get lower breakdown pressure and enhance fracture complexity & CO2 exists in dense phase at static bottom hole conditions, thus is less susceptible to dissipation and dissolves in crude oil which reduces its viscosity and improves cleanup and recovery.
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Feng, Jin-yang, Xiong-ying Ye, Yuan-fang Shang, Kang Wu, and Feng Chen. "Integrated dual grating polymer microbeams for bio-chemical sensing in liquid environment." In 2013 8th IEEE International Conference on Nano/Micro Engineered and Molecular Systems (NEMS). IEEE, 2013. http://dx.doi.org/10.1109/nems.2013.6559935.

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Liu, Songyuan, Bo Lu, Chao-yu Sie, and Yifan Li. "Bioremediation by Indigenous Microbes: A Green Approach to Degrade Polymer Residue." In SPE Improved Oil Recovery Conference. SPE, 2022. http://dx.doi.org/10.2118/209422-ms.

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Abstract Polyacrylamide-based friction reducer is commonly used in well completion for unconventional reservoirs. However, residual polymer trapped in the near well-bore region could create unintended flow restrictions and could negatively impact oil production. An eco-friendly approach to regain conductivity was developed by stimulating indigenous bacteria for residual polymer biodegradation. In this work, a series of laboratory experiments were conducted using produced water and oil from Permian Basin, polyacrylamide-based polymer, and a modified nutrient recipe that contained 100 to 300 ppm of inorganic salts. The sealed sample vials containing water, oil, and polymer were prepared in a sterilized anaerobic chamber and then kept in a 160° F incubator to simulate the reservoir condition. Feasibility tests of bacteria growth and biodegradation evaluation of polymer were conducted using an optical laser microscopic system with bacteria tagged with fluorescent dye. Size regression was calculated and applied to a mathematical model based on actual fracture aperture distribution data from shale formation. The indigenous bacteria were successfully stimulated with and without the existence of the friction reducer. It was observed that the size of polymer particles decreased from over 300 µm to less than 20 µm after 15 days. Under the condition of produced water injection, 140° F reservoir temperature, and anaerobic environment, about 30% of the natural fractures in shale were calculated to be damaged and remediated within 15 days. This work is a pioneer research on microbial EOR application in unconventional reservoirs with only indigenous bacteria involved. In field applications, only an extremely low amount of nutrient is required in this process which provides great economic potential. Additionally, the nutrients introduced into the reservoirs will be fully consumed by bacteria during treatment, and the bacteria will be decomposed into organic molecules soon after the treatment. Thus, this technique is environmental- and economical- friendly for the purpose of polymer damage remediation to maximize the recoverable.
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Bouchaala, Adam, Ali H. Nayfeh, Nizar Jaber, and Mohammad I. Younis. "Mass and Position Determination in MEMS Resonant Mass Sensors: Theoretical and Experimental Investigation." In ASME 2016 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/detc2016-59813.

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We present a method to determine accurately the position and mass of an entity attached to the surface of an electrostatically actuated clamped-clamped microbeam implemented as a mass sensor. In the theoretical investigation, the microbeam is modeled as a nonlinear Euler-Bernoulli beam and a perturbation technique is used to develop a closed-form expression for the frequency shift due to an added mass at a specific location on the microbeam surface. The experimental investigation was conducted on a microbeam made of Polyimide with a special lower electrode to excite both of the first and second modes of vibration. Using an ink-jet printer, we deposited droplets of polymers with a defined mass and position on the surface of the microbeam and we measured the shifts in its resonance frequencies. The theoretical predictions of the mass and position of the deposited droplets match well with the experimental measurements.
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Zielke, Mark A., Andrew Morrill, Barry Demartini, Martin Moskovits, and Kimberly Turner. "Polymer Coated Tin Oxide Nanowires for Improved Sensitivity of MEMS Chemical Sensors Based on Microbeams." In ASME 2008 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/detc2008-49843.

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MEMS mass sensors are an important field of study for chemical and biological sensing. We utilize the massive surface area to volume ratio of tin oxide nanowires to improve the sensing characteristics of resonant cantilever gas sensors. The nanowires are grown onto released silicon cantilevers via the vapor liquid solid method, a type of chemical vapor deposition. Through intelligent catalyst placement the nanowires are grown selectively onto predefined surfaces of the cantilever. The increased surface area of our nanowire coatings provides greatly increased active binding area for analytes, while high quality factors are still achieved with this method. Our experiments actively monitor the removal of a silane self assembled monolayer from the sensor surface. Current nanowire coated sensors show a tenfold increase in sensitivity when compared to the bare sensors. We have functionalized the nanowires with a variety of polymer coatings. These functionalized sensors also show a substantial increase in sensitivity to the analytes. By varying the polymer coating applied to the nanowires, a sensor array can be generated that achieves gas recognition while having incorporated the increased sensitivity of the nanowire coatings.
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Reports on the topic "Polymer microbeads"

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Ding, Zheng-You, Shenmin Ma, Dennis Kriz, J. J. Aklonis, and R. Salovey. Model Filled Polymers .11. Synthesis of Uniformly Crosslinked Polystyrene Microbeads. Fort Belvoir, VA: Defense Technical Information Center, June 1991. http://dx.doi.org/10.21236/ada237472.

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Holthoff, Ellen L., Lily Li, Tobias Hiller, and Kimberly L. Turner. A Molecularly Imprinted Polymer (MIP)-Coated Microbeam MEMS Sensor for Chemical Detection. Fort Belvoir, VA: Defense Technical Information Center, September 2015. http://dx.doi.org/10.21236/ada622335.

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