Literatura académica sobre el tema "Formulated capillary product"
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Artículos de revistas sobre el tema "Formulated capillary product":
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Sahu, Nisha, Sukrita Shriwas, Yeendeswari Gendre, Aakanksha Sinha y S. J. Daharwal. "A Review on Various Analytical Methodologies of Naproxen". Journal of Ravishankar University (PART-B) 36, n.º 1 (13 de julio de 2023): 94–103. http://dx.doi.org/10.52228/jrub.2023-36-1-9.
Resumen
Naproxen is a Nonsteroidal Anti-Inflammatory Drug (NSAID). It is mostly used to treat pain or inflammation caused by conditions such as arthritis, gout, tendinitis or menstrual cramps. Naproxen is available in isolated dose with various similar anti-inflammatory drugs, i.e.; esomeprazole, pantoprazole, paracetamol, ranitidine, sumatriptan and ibuprofen. This survey evaluates various methods for the analysis of Naproxen in bulk drugs and formulated products. Analytical procedures are critical for determining compositions, they allow as to obtain both qualitative and quantitative results utilizing by the advanced analytical tools. This include HPLC, HPTLC, UV- spectrophotometry, capillary electrophoresis, and electrochemical meth-ods. The UV-spectrophotometry method is applied for the investigation of Naproxen in biologi-cal media, bulk samples and in various dosage formulations. The HPLC technique of Naproxen alone and the combination, including parameters such as matrix, stationary phase, mobile phase, wavelength detection, etc. HPTLC method parameters such as stationary phase, mobile combi-nation phase, RF value, etc. To maintain high commercial product quality standards and to ad-here to regulatory requirements, analytical technique development is necessary. Drug concen-trations are measured using bioanalytical techniques. Development and validation of bioanalyt-ical method is important to understand the pharmacokinetics of any drug and/or its metabolites.
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Mahuzie, Pierre-Etienne, Brian J. Clark, Andy J. Crumpton y Kevin D. Altria. "Quantitative microemulsion electrokinetic capillary chromatography analysis of formulated drug products". Journal of Separation Science 24, n.º 9 (1 de septiembre de 2001): 784–88. http://dx.doi.org/10.1002/1615-9314(20010901)24:9<784::aid-jssc784>3.0.co;2-2.
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Kahn, Bobbi B. y David F. Tomkins. "Determination of Acetochlor in Technical and Formulated Products by Capillary Gas Chromatography". Journal of AOAC INTERNATIONAL 84, n.º 2 (1 de marzo de 2001): 317–22. http://dx.doi.org/10.1093/jaoac/84.2.317.
Resumen
Abstract A peer-verified gas chromatographic (GC) method is presented for the weight percent (wt %) determination of acetochlor herbicide in technical and formulated products. During method development, the method was found to be rugged by the Youden Ruggedness Test. Two laboratories with experience in the wt % determination of acetochlor in various matrixes participated in this study. Each laboratory received 10 blind duplicate test samples of the following 5 matrixes: one acetochlor technical and 4, different, emulsifiable concentrate (EC) formulations—Harness® EC (MON 5841), Harness ® Export/Fist (MON 8435), Surpass® EC (HF), and Surpass ® EC (LF). Each participant was asked to make duplicate weighings of each of the test samples and to inject each test sample solution twice. All test samples were analyzed on the same day, and 8 data points (replicates) per matrix were obtained. The test samples were dissolved in acetone that contained dipentyl phthalate as an internal standard. They were analyzed by GC on a 15 m capillary column by using split injection and a flame ionization detector. Acetochlor (wt %) was determined by comparing the ratios of peak area of acetochlor/peak area of dipentyl phthalate internal standard obtained for the test sample and calibration solutions. Repeatability of the method, expressed as the within-laboratory (between replicates) relative standard deviation (RSDr), was found to be 0.09–0.77% for the 5 matrixes. Reproducibility of the method, expressed as the within-test sample relative standard deviation (RSDR), was found to be 0.18–0.78% for the 5 matrixes.
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Lo, Chi-Chu, Yuh-Jyuan Lee y Chai-Ju Chang. "High-Performance Capillary Electrophoretic Method for the Determination of Blasticidin S in Formulated Products". Journal of Agricultural and Food Chemistry 43, n.º 11 (noviembre de 1995): 2892–95. http://dx.doi.org/10.1021/jf00059a023.
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Masukawa, Yoshinori. "Separation and determination of basic dyes formulated in hair care products by capillary electrophoresis". Journal of Chromatography A 1108, n.º 1 (marzo de 2006): 140–44. http://dx.doi.org/10.1016/j.chroma.2006.01.007.
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Kikta, Edward J., O. O. Bennett, L. Bradbury, P. Coco, K. Henley, A. Hernandez, R. Larson et al. "Gas Chromatographic Determination of Bifenthrin in Technical and Selected Formulated Products: Collaborative Study". Journal of AOAC INTERNATIONAL 94, n.º 2 (1 de marzo de 2011): 453–58. http://dx.doi.org/10.1093/jaoac/94.2.453.
Resumen
Abstract A GC method for the analysis of technical and formulated bifenthrin samples was evaluated in a collaborative study. Bifenthrin is determined by using a 50 (trifluoropropyl)-methylpolysiloxane wide-bore capillary column and flame ionization detector. Ten samples, consisting of four formulations and a technical material were analyzed by 12 collaborators using Youden pairs. The four formulation types included in this study were microemulsion (ME), wettable powder (WP), suspension concentrate (SC), and emulsifiable concentrate (EC). Variability in the analysis of two of the formulation types, SC and EC, was later found to be due to the noncommercial containers used to hold the test samples. Because of this, valid data could not be obtained for the EC and SC. For the two formulations for which valid data could be obtained, ME and WP, and the technical chemical, accuracy and variability results are typical of large data sets. For the technical chemical and the two formulations for which valid data were obtained, Official First Action is recommended.
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Lo, Chi-Chu y Yi-Min Hsiao. "High-Performance Capillary Electrophoretic Method for the Determination of Antibiotic Fungicide Kasugamycin in Formulated Products". Journal of Agricultural and Food Chemistry 44, n.º 8 (enero de 1996): 2231–34. http://dx.doi.org/10.1021/jf9601675.
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Vargyas, Linda D., Gregory E. Walls, Richard L. Cryberg, William R. Bramstedt, Frank J. Wang, Hugh L. Mayo y Gary L. Eilrich. "Simultaneous Determination of Chlorothalonil and Hexachlorobenzene in Technical and Formulated Materials by Capillary Gas Chromatography". Journal of AOAC INTERNATIONAL 78, n.º 3 (1 de mayo de 1995): 604–9. http://dx.doi.org/10.1093/jaoac/78.3.604.
Resumen
Abstract A capillary gas chromatographic method using flame ionization detection was developed for simultaneous assay of chlorothalonil and hexachlorobenzene in technical material and formulated products. Method precision is excellent, and the method allows simultaneous determination of one chemical impurity. The method uses an internal normalization reagent (n-butyl phthalate). Modification and extension of the method to formulated products, including wettable powders, water-based flowables, and dispersible (or dry flowable) granular formulations, are discussed. Preliminary statistical analysis of intra- and interlaboratory comparisons was performed to evaluate method ruggedness. Average relative standard deviations for technical materials were 0.34 and 0.17% from 2 laboratories. Additional method validation studies were conducted to examine the influence of pH, solvent systems, gas chromatographic systems, and temperature conditions on different formulations.
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Di Rosa, Claudia, Elisa De Arcangelis, Virginia Vitelli, Salvatore Crucillà, Martina Angelicola, Maria Carmela Trivisonno, Francesco Sestili et al. "Effect of Three Bakery Products Formulated with High-Amylose Wheat Flour on Post-Prandial Glycaemia in Healthy Volunteers". Foods 12, n.º 2 (9 de enero de 2023): 319. http://dx.doi.org/10.3390/foods12020319.
Resumen
Both Glycaemic index (GI) and Glycaemic Load (GL) were introduced to measure the impact of a carbohydrate-containing food on blood glucose. From this perspective, high-amylose (HA) flours, with a higher percentage of resistant starch (RS), may represent a suitable raw material to improve the glycaemic response. The present work aims to investigate the GI of HA bakery products (biscuits, taralli and bread) compared to products obtained from conventional flour. Ten healthy volunteers were enrolled and their capillary blood glucose was measured every 15 min for 2 h after the consumption of HA and control products containing 50 g of available carbohydrates. On average, in the three bakery products, the amount of total starch replaced by RS was equal to 12%. HA biscuits and HA bread showed significantly lower GI than their control counterparts (p = 0.0116 and p = 0.011, respectively) and better glycaemic control. From the survey to assess liking and willingness to pay on HA snacks, HA packages received an average premium of €0.66 compared to control products. Although HA flour results in lower GI in both biscuits and bread, further studies are needed to evaluate the correct composition of HA products to have beneficial effects on post-prandial glycaemia.
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Vladimirova, Daria, Vladimir Pervadchuk y Yuri Konstantinov. "Manufacture of Microstructured Optical Fibers: Problem of Optimal Control of Silica Capillary Drawing Process". Computation 12, n.º 5 (23 de abril de 2024): 86. http://dx.doi.org/10.3390/computation12050086.
Resumen
The effective control of any technological process is essential in ensuring high-quality finished products. This is particularly true in manufacturing knowledge-intensive and high-tech products, including microstructured photonic crystal fibers (PCF). This paper addresses the issues of stabilizing the optimal control of the silica capillary drawing process. The silica capillaries are the main components of PCF. A modified mathematical model proposed by the authors is used as the basic model of capillary drawing. The uniqueness of this model is that it takes into account the main forces acting during drawing (gravity, inertia, viscosity, surface tension, pressure inside the drawn capillary), as well as all types of heat transfer (heat conduction, convection, radiation). In the first stage, the system of partial differential equations describing heat and mass transfer was linearized. Then, the problem of the optimal control of the drawing process was formulated, and optimization systems for the isothermal and non-isothermal cases were obtained. In the isothermal case, optimal adjustments of the drawing speed were obtained for different objective functionals. Thus, the proposed approach allows for the constant monitoring and adjustment of the observed state parameters (for example, the outer radius of the capillary). This is possible due to the optimal control of the drawing speed to obtain high-quality preforms. The ability to control and promptly eliminate geometric defects in the capillary was confirmed by the analysis of the numerical calculations, according to which even 15% deviations in the outer radius of the capillary during the drawing process can be reduced to 4–5% by controlling only the capillary drawing speed.
Tesis sobre el tema "Formulated capillary product":
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Dupeux, Tristan. "Integrated in silico and in vitro approaches to investigate the physicochemical phenomena induced by fragrances in micellar aqueous solutions and foams". Electronic Thesis or Diss., Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUR053.
Resumen
Le parfum est un composant majeur des formulations de produits d'hygiène dont la perception et l'intensité impactent fortement l'opinion du consommateur quant à leur efficacité et leur appréciation. Déposer un parfum sur les cheveux de façon durable ou contrôler sa libération pendant l'utilisation sont de véritables défis technologiques et scientifiques pour le formulateur et le physicochimiste. La libération à long terme peut être efficacement assurée par les capsules de parfum qui ont apporté une solution technologique viable mais l'explosion de l'odeur recherchée pendant l'utilisation n'est pas encore suffisamment maîtrisée. Dans ce contexte, nous nous sommes intéressés à comprendre le comportement des molécules de parfum dans une matrice complexe, telles que celles rencontrées dans les shampooings, depuis la solution aqueuse micellaire riche en tensioactifs jusqu’à la formation de la mousse après dilution, afin d’identifier les leviers physicochimiques permettant d’exalter le relargage du parfum. En combinant approches analytiques et prédictives, nous avons étudié les interactions des molécules de parfums avec les tensioactifs et avec les sels. La chromatographie en phase gazeuse dans l'espace de tête (HS-GC), la RMN DOSY et le logiciel COSMOmic ont été des outils utiles pour corréler la concentration des molécules de parfum dans l'air avec la fraction solubilisée et leur positionnement dans le système micellaire. L’addition de sels modifie complètement les propriétés de la solution aussi bien au niveau des micelles que du parfum. La libération de ce dernier dépend principalement de la nature des ions et de la concentration du parfum dans l'eau tout en restant indépendante à la viscosité du système. Les méthodes COSMO-RS-ES (adaptée aux solutions salées) et COSMOplex (adaptée aux micelles) ont fourni des prédictions raisonnables de la répartition du parfum mesurée expérimentalement dans de tels systèmes. Enfin, une analyse de faisabilité a été réalisée pour étudier l'importance des propriétés et de la structure de la mousse pour améliorer la diffusion du parfum dans l'airFragrance is a major component of personal care product formulations, whose perception and intensity have a strong impact on the consumer's opinion of their effectiveness and appreciation. Depositing a fragrance on the hair in a durable way or controlling its release during in-use are serious technological and scientific challenges for the formulator and the physicochemist. Long-term release can be effectively ensured by perfume capsules which have provided a reliable technological solution, but the desired scent burst during the product use is not yet sufficiently mastered. In this context, we focused on understanding the behavior of fragrance molecules in a complex matrix, such as those found in shampoos, from the surfactant-rich aqueous micellar solution to the formation of foam after dilution, in order to identify the physicochemical levers to exalt the release of fragrance. By combining analytical and predictive approaches, we studied the interactions of fragrance molecules with surfactants and salts. Headspace gas chromatography (HS-GC), DOSY NMR and COSMOmic software were useful tools to correlate the concentration of fragrance molecules in air with the solubilized fraction and their positioning in the micellar system. The addition of salts completely modifies the properties of the solution at the level of the micelles as well as the perfume. The release of the latter depends mainly on the nature of the ions and the concentration of the perfume in the water while remaining independent of the viscosity of the system. The COSMO-RS-ES (adapted to salt solutions) and COSMOplex (adapted to micelles) methods provided reasonable predictions of the experimentally measured fragrance partition in such systems. Finally, a feasibility analysis was performed to investigate the importance of foam properties and structure in enhancing airborne fragrance diffusion
Actas de conferencias sobre el tema "Formulated capillary product":
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Gonser, Michael, Bridgette Allan y Jonathan Wylde. "Simultaneous Control of Subsurface Scale, Corrosion, and H2S Using a Single Capillary String: A Real-World Chemical Application in the Permian Basin". En SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210140-ms.
Resumen
Abstract This paper details the laboratory development and subsequent field trial of a Downhole, Non-Triazine H2S Scavenger (DNTS) that was co-injected via a single capillary string (cap-string) with the incumbent scale/corrosion inhibitor (CI/SI) combination product. The target sour producer wells were configured with single cap-strings, and it was considered critical that H2S suppression was moved upstream downhole in high-risk sour producers to improve overall control of H2S in those wells and across the topsides process. The dual injection approach was preferred to ‘1-can’ injection (all production chemicals formulated into one fluid package) as it allowed targeting and more effective use of chemicals deployed for control of corrosion, scale and H2S within the receiving wells and for the topside process. Product evolution followed classic laboratory development routes, utilizing industry standard performance techniques for scale, corrosion, and H2S scavenger assessment. Particular emphasis was placed on inter-chemical and ‘multiple chemical active’-material compatibilities for downhole co-injection and return to topsides with production. Three gas-lifted wells currently supported by CI/SI dosing via cap-string were selected for field trial based on their H2S levels. A three-phase approach was followed, with Phase I providing initial proof-of-concept validation of the dual application technique in Well A; and in Phase II the technique was rolled out to Wells B and C to demonstrate the techniques versatility when applied to adjacent wells that had different CI/SI and scavenger requirements. Phase III provided the ultimate test when the three trial wells were dosed simultaneously and the impact on topsides process H2S control was assessed with reference to meeting the all-important facility prescribed daily operational allowed H2S target. The laboratory testing phase confirmed that the products (DNTS and CI/SI) could be safely deployed downhole together via the same injection string, and chemical-chemical and chemical-materials compatibility issues were determined to be negligible. Field trialing showed scale and corrosion inhibition to be unaffected by the dual injection (via routine residuals monitoring), and scavenger performance metrics (as sampled at the wellhead) during steady-state production and treatment indicated impressive scavenging performance. Injection of DNTS downhole resulted in rapid impact on topsides H2S, and wellhead H2S samples indicated almost two orders of magnitude of improvement in H2S control with reduction from 1000 ppm to <10 ppm achieved. The co-injection of DNTS and CI/SI assured management of scale, corrosion and H2S within the target wells from point of injection up to surface, and then onto process. Consequently, topside MEA-triazine dosing was reduced, reflecting the lower H2S levels observed, and overall, the dual downhole deployment clearly improved downhole and topside control of H2S. The reduced requirement for MEA-triazine promised significant operational cost-savings besides chalking up a sizeable Environmental, Social, and Governance (ESG) CO2 intensity ‘win’ due to massively reducing the incumbent (MEA-triazine) chemical usage. The co-injection of scale, corrosion, and H2S treatments via single capillary met H2S production specifications for three different sour gas-lift wells and at process export, while improving asset integrity within subsurface equipment, improved safer operating conditions for personnel topsides, reduced corrosive liquid handling issues, and greatly increased the value of the export sales gas via H2S specification management.
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Chung, Dennis. "Elucidation of Sealing Mechanism of Novel Acrylate Liquid Based BluSeal <sup>TM</sup> Wire Harness Splice Sealing Technology". En WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2024. http://dx.doi.org/10.4271/2024-01-2356.
Resumen
<div class="section abstract"><div class="htmlview paragraph">Unlike conventional heat shrink tubes or enclosure systems which only seals wires and splices on the outside, a novel Acrylate based sealing technology developed and introduced by Eurotech is a low viscosity fluid formulated to be applied to the splices either in liquid droplets or by dipping, utilizes fast capillary-wicking action and quick self-cure inside the wires to form a robust, cost effective, flexible, impenetrable seal to prevent moisture damage of wire harnesses and associated electrical components. This technology is an enabler of new wire harness architectures currently limited by the shortcomings of conventional sealing products such as heat shrink tubes which come up short when the splice configurations or geometries become too complex or difficult for sealing from the outside.</div><div class="htmlview paragraph">Sealing mechanism investigation was launched and the results of the analytical experiments are presented to reveal how this unique sealing technology works to effectively withstand pneumatic air bubble pressure applied to the wires thus demonstrating effective prevention of water ingress into the wires. Surface energy analysis performed for this sealing liquid against metal and plastic surfaces is presented to confirm the capillary action observed within wires. Real-time FTIR data confirmed its fast cure kinetics which also supports the proposed hypothesis of the interfacial cure initiation and solid front growth phenomena inside the wires. Cross sectional microscopy and sealing depth profiling investigations point to the synergy of capillary action, fast cure kinetics combined with robust adhesive chemistry of this sealing system as primary contributors to achieving a durable, robust in-wire sealing capability of this technology. Automotive OEM performance specification test results for sealing performance and long-term durability of this technology are also presented.</div></div>
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Bian, Y., P. T. Chiang, S. Kiran, D. Wiebe y D. Oswald. "Lab Study of High WAT Wax Deposition Reduction with Wax Inhibitors and Dispersants". En SPE Annual Technical Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/215043-ms.
Resumen
Abstract Canadian crude oil and pigged wax from the Montney formation show high wax appearance temperatures (WAT) and experience severe deposition issues during production and transportation. Several commercial wax inhibitors and wax dispersants were studied in the crude oil and reconstituted oils (pigged wax added back to the crude oil and dodecane model system), to minimize the wax deposition by a systematic lab screening protocol. Suitable wax inhibitors (WI) and dispersants were selected and formulated at optimized dosage to efficiently reduce the wax deposition at close to field condition. The crude oil and reconstituted oils were utilized to study the high WAT wax performance with different types of wax inhibitors and dispersants. This included ethylene vinyl acetate (EVA), alkylphenol formaldehyde resin (AFR), acrylic copolymer (AC), α-olefin maleic anhydride copolymer (AOMAC) and several surfactant-based wax dispersants (WDs). A pour point tester was employed as the initial screening tool to determine the pour point and detected wax appearance temperature (DWAT). Multiple Light Scattering (MLS) was used to evaluate the dispersions of wax in the oil. Dynamic wax deposition tests by capillary flow through (CFT) and dynamic flow loop (DFL) systems were used to verify the wax deposition reduction efficiency, and to study the effect of the test parameters on wax deposition. The reconstituted oils had higher WAT (>55 °C) than produced oil. The screening tests showed that EVA significantly reduced the DWAT and pour point of the crude oil but was not very efficient in the reconstituted oil. Both AFR and AC reduced the DWAT and pour point but were not as efficient as AOMAC. AOMAC provided the lowest DWAT in the reconstituted oil. It was interesting to find that surfactant-based dispersants also reduced the DWAT of the reconstituted model oil. The top performing WIs and dispersants were then tested by CFT wax deposition system at a flowrate of 1.5 cm3/hr. For the crude oil at 10 °C, 225 ppm AOMAC WI was needed to efficiently reduce the wax deposition in the CFT system. A lower dosage was required in the DFL system. It was also found that wax inhibitor and dispersant together further reduced the reconstituted model oil wax deposition in the CFT system. MLS and bottle tests showed that the WDs helped to disperse the wax in both oil and aqueous phases. From this systematic WI study on kinetic and dynamic behaviors of high WAT wax deposition, a synergy was observed between wax inhibitors and dispersants. Further investigation is needed to understand how they work together. The specially designed laboratory screening protocol helped to understand the structure and performance relation, efficiently formulate the WIs/dispersants, and optimize the treatment dosages. The inclusion of surfactants/dispersants with WIs could further mitigate wax deposition and be a more cost-effective approach.
Informes sobre el tema "Formulated capillary product":
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Snyder, Victor A., Dani Or, Amos Hadas y S. Assouline. Characterization of Post-Tillage Soil Fragmentation and Rejoining Affecting Soil Pore Space Evolution and Transport Properties. United States Department of Agriculture, abril de 2002. http://dx.doi.org/10.32747/2002.7580670.bard.
Resumen
Tillage modifies soil structure, altering conditions for plant growth and transport processes through the soil. However, the resulting loose structure is unstable and susceptible to collapse due to aggregate fragmentation during wetting and drying cycles, and coalescense of moist aggregates by internal capillary forces and external compactive stresses. Presently, limited understanding of these complex processes often leads to consideration of the soil plow layer as a static porous medium. With the purpose of filling some of this knowledge gap, the objectives of this Project were to: 1) Identify and quantify the major factors causing breakdown of primary soil fragments produced by tillage into smaller secondary fragments; 2) Identify and quantify the. physical processes involved in the coalescence of primary and secondary fragments and surfaces of weakness; 3) Measure temporal changes in pore-size distributions and hydraulic properties of reconstructed aggregate beds as a function of specified initial conditions and wetting/drying events; and 4) Construct a process-based model of post-tillage changes in soil structural and hydraulic properties of the plow layer and validate it against field experiments. A dynamic theory of capillary-driven plastic deformation of adjoining aggregates was developed, where instantaneous rate of change in geometry of aggregates and inter-aggregate pores was related to current geometry of the solid-gas-liquid system and measured soil rheological functions. The theory and supporting data showed that consolidation of aggregate beds is largely an event-driven process, restricted to a fairly narrow range of soil water contents where capillary suction is great enough to generate coalescence but where soil mechanical strength is still low enough to allow plastic deforn1ation of aggregates. The theory was also used to explain effects of transient external loading on compaction of aggregate beds. A stochastic forInalism was developed for modeling soil pore space evolution, based on the Fokker Planck equation (FPE). Analytical solutions for the FPE were developed, with parameters which can be measured empirically or related to the mechanistic aggregate deformation model. Pre-existing results from field experiments were used to illustrate how the FPE formalism can be applied to field data. Fragmentation of soil clods after tillage was observed to be an event-driven (as opposed to continuous) process that occurred only during wetting, and only as clods approached the saturation point. The major mechanism of fragmentation of large aggregates seemed to be differential soil swelling behind the wetting front. Aggregate "explosion" due to air entrapment seemed limited to small aggregates wetted simultaneously over their entire surface. Breakdown of large aggregates from 11 clay soils during successive wetting and drying cycles produced fragment size distributions which differed primarily by a scale factor l (essentially equivalent to the Van Bavel mean weight diameter), so that evolution of fragment size distributions could be modeled in terms of changes in l. For a given number of wetting and drying cycles, l decreased systematically with increasing plasticity index. When air-dry soil clods were slightly weakened by a single wetting event, and then allowed to "age" for six weeks at constant high water content, drop-shatter resistance in aged relative to non-aged clods was found to increase in proportion to plasticity index. This seemed consistent with the rheological model, which predicts faster plastic coalescence around small voids and sharp cracks (with resulting soil strengthening) in soils with low resistance to plastic yield and flow. A new theory of crack growth in "idealized" elastoplastic materials was formulated, with potential application to soil fracture phenomena. The theory was preliminarily (and successfully) tested using carbon steel, a ductile material which closely approximates ideal elastoplastic behavior, and for which the necessary fracture data existed in the literature.