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1.
Felipe A. Perdomo Siti H. Khalit Claire S. Adjiman Amparo Galindo George Jackson 《American Institute of Chemical Engineers》2021,67(3):e17194
The SAFT-γ Mie group-contribution equation of state is used to represent the fluid-phase behavior of aqueous solutions of a variety of linear, branched, and cyclic amines. New group interactions are developed in order to model the mixtures of interest, including the like and unlike interactions between alkyl primary, secondary, and tertiary amine groups (NH2, NH, N), cyclic secondary and tertiary amine groups (cNH, cN), and cyclic methine-amine groups (cCHNH, cCHN) with water (H2O). The group-interaction parameters are estimated from appropriate experimental thermodynamic data for pure amines and selected mixtures. By taking advantage of the group-contribution nature of the method, one can describe the fluid-phase behavior of mixtures of molecules comprising those groups over broad ranges of temperature, pressure, and composition. A number of aqueous solutions of amines are studied including linear, branched aliphatic, and cyclic amines. Liquid–liquid equilibria (LLE) bounded by lower critical solution temperatures (LCSTs) have been reported experimentally and are reproduced here with the SAFT-γ Mie approach. The main feature of the approach is the ability not only to represent accurately the experimental data employed in the parameter estimation, but also to predict the vapor–liquid, liquid–liquid, and vapor–liquid–liquid equilibria, and LCSTs with the same set of parameters. Pure compound and binary phase diagrams of diverse types of amines and their aqueous solutions are assessed in order to demonstrate the main features of the thermodynamic and fluid-phase behavior. 相似文献
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Volatile fatty acids production from cheese whey: influence of pH,solid retention time and organic loading rate 下载免费PDF全文
4.
Lianfeng Zhao Kwangdong Roh Sara Kacmoli Khaled Al Kurdi Samik Jhulki Stephen Barlow Seth R. Marder Claire Gmachl Barry P. Rand 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):2000752
The performance of lead-halide perovskite light-emitting diodes (LEDs) has increased rapidly in recent years. However, most reports feature devices operated at relatively small current densities (<500 mA cm−2) with moderate radiance (<400 W sr−1 m−2). Here, Joule heating and inefficient thermal dissipation are shown to be major obstacles toward high radiance and long lifetime. Several thermal management strategies are proposed in this work, such as doping charge-transport layers, optimizing device geometry, and attaching heat spreaders and sinks. Combining these strategies, high-performance perovskite LEDs are demonstrated with maximum radiance of 2555 W sr−1 m−2, peak external quantum efficiency (EQE) of 17%, considerably reduced EQE roll-off (EQE > 10% to current densities as high as 2000 mA cm−2), and tenfold increase in operational lifetime (when driven at 100 mA cm−2). Furthermore, with proper thermal management, a maximum current density of 2.5 kA cm−2 and an EQE of ≈1% at 1 kA cm−2 are shown using electrical pulses, which represents an important milestone toward electrically driven perovskite lasers. 相似文献
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Yin Bao Lie Tang Matthew W. Breitzman Maria G. Salas Fernandez Patrick S. Schnable 《野外机器人技术杂志》2019,36(2):397-415
Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study demonstrated the suitability of stereo vision for field‐based three‐dimensional plant phenotyping when recent advances in stereo matching algorithms were incorporated. A robust data processing pipeline was developed to quantify the variations or morphological traits in plant architecture, which included plot‐based plant height, plot‐based plant width, convex hull volume, plant surface area, and stem diameter (semiautomated). These image‐derived measurements were highly repeatable and showed high correlations with the in‐field manual measurements. Meanwhile, manually collecting the same traits required a large amount of manpower and time compared to the robotic system. The results demonstrated that the proposed system could be a promising tool for large‐scale field‐based high‐throughput plant phenotyping of bioenergy crops. 相似文献
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Mine Water and the Environment - Reducing the amount of water in a milled tailings storage facility (TSF) is the primary way to reduce the risk of a catastrophic failure. In addition, a significant... 相似文献
7.
William M. Pitts Martin Werrel Marco Fernandez Mary A. Long Evan A. Eisenberg James Filliben Cory D. Runyon 《火与材料》2021,45(1):127-154
Fire spread and growth on real‐scale four cushion mock‐ups of residential upholstered furniture (RUF) were investigated with the goal of identifying whether changes in five classes of materials (barrier, flexible polyurethane foam, polyester fiber wrap, upholstery fabric, and sewing thread), referred to as factors, resulted in statistically significant changes in burning behavior. A fractional factorial experimental design plus practical considerations yielded a test matrix with 20 material combinations. Experiments were repeated a minimum of two times. Measurements included fire spread rates derived from video recordings and heat release rates (HRRs). A total of 13 experimental parameters (3 based on the videos and 10 on the HRR results), referred to as responses, characterized the measurements. Statistical analyses based on Main Effects Plots (main effects) and Block Plots (main effects and factor interactions) were used. The results showed that three of the factors resulted in statistically significant effects on varying numbers of the 13 responses. The Barrier and Fabric factors had the strongest main effects with roughly comparable magnitudes. Foam was statistically significant for fewer of the responses and its overall strength was weaker than for Barrier and Fabric. No statistically significant main effects were identified for Wrap or Thread. Multiple two‐term interactions between factors were identified as being statistically significant. The Barrier*Fabric interaction resulted in the highest number of and strongest statistically significant effects. The existence of two‐term interactions means that it will be necessary to consider their effects in approaches designed to predict the burning behavior of RUF. 相似文献
8.
Engel Robert Fernandez Pablo Ruiz-Cortes Antonio Megahed Aly Ojeda-Perez Juan 《Information Systems and E-Business Management》2022,20(1):199-221
Information Systems and e-Business Management - Service providers compose services in service chains that require deep integration of core operational information systems across organizations.... 相似文献
9.
Anja Schrder Joris Sprakel Karin Schroën Claire C. Berton‐Carabin 《European Journal of Lipid Science and Technology》2020,122(6)
Colloidal lipid particles (CLPs) are promising encapsulation systems for lipophilic bioactives, such as oil‐soluble antioxidants that are applied in food and pharmaceutical formulations. Currently, there is no clear consensus regarding the relation between particle structure and the chemical stability of such bioactives. Using α‐tocopherol as a model antioxidant, it is shown that emulsifier type (Tween 20 or 40, or sodium caseinate) and lipid composition (tripalmitin, tricaprylin, or combinations thereof) modulated particle morphology and antioxidant stability. The emulsifier affects particle shape, with the polysorbates facilitating tripalmitin crystallization into highly ordered lath‐like particles, and sodium caseinate resulting in less ordered spherical particles. The fastest degradation of α‐tocopherol is observed in tripalmitin‐based CLPs, which may be attributed to its expulsion to the particle surface induced by lipid crystallization. This effect is stronger in CLPs stabilized by Tween 40, which may act as a template for crystallization. This work not only shows how the architecture of CLPs can be controlled through the type of lipid and emulsifier used, but also gives evidence that lipid crystallization does not necessarily protect entrapped lipophilic bioactives, which is an important clue for encapsulation system design. Practical Applications: Interest in enriching food and pharmaceutical products with lipophilic bioactives such as antioxidants through encapsulation in lipid particles is growing rapidly. This research suggests that for efficient encapsulation, the particle architecture plays an important role; to tailor this, the contribution of both the lipid carrier and the emulsifier needs to be considered. 相似文献
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