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Reginald E. Rogers Garry M. Clarke Olivia N. Matthew Matthew J. Ganter Roberta A. DiLeo Jason W. Staub Michael W. Forney Brian J. Landi 《Journal of Applied Electrochemistry》2013,43(3):271-278
Lithium transition metal phosphates have the capability of improving cathode energy densities up to 800 Wh kg?1, a 27 % increase over conventional cathode active material energy densities. In this study, the effect of base-to-acid (NH4OH:H3PO4) stoichiometric conditions on the intrinsic reversible capacity of lithium cobalt phosphate (LiCoPO4) active material are investigated through microwave synthesis and electrochemical testing. Variation in solution pH results in an increase of 69 mAh g?1 in achievable capacity. X-ray diffraction results show highly crystalline LiCoPO4, with particle sizes ranging from 200 nm to greater than 1 μm based upon scanning electron microscopy. Electrochemical analysis with 1 M LiPF6 EC:EMC (1:2 v/v) provides the highest capacity over multiple cycles. A discharge capacity of 128 mAh g?1 (78 % of theoretical capacity) is achievable for intrinsic LiCoPO4 without further treatment (e.g., carbon coating) at an effective 0.1 C rate with a proper constant current–constant voltage step. Analysis of reported synthesis techniques shows that microwave synthesis yields the highest capacity for the intrinsic LiCoPO4 material to date. 相似文献
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Olivia V. López Noemí E. Zaritzky María V.E. Grossmann María A. García 《Journal of food engineering》2013
Thermoplastic starch (TPS) materials were developed from mixtures of native and acetylated corn starches with glycerol. To optimize the formulations an experimental design for multicomponent mixtures was used and the assayed formulations were determined by statistical software. Blends and pellets humidity content increased with glycerol concentration. Starch destructuration during the extrusion process was studied by thermal analysis. Films presented homogenous structure, rough surfaces and certain stickiness. They presented different properties, related mainly to the differential characteristics of native and acetylated starches and to hydrophilic character of glycerol. Their mechanical behavior indicated that they are a good option as a food packaging materials since TPS films resulted enough resistant to protect the product and flexible to resist moderate deformations. Besides, the use of acetylated starch in the formulations enhanced film resistance and reduced their WVP, despite of its low modification degree. The storage of the films under controlled conditions increased their stiffness, while their flexibility and WVP were reduced. Plasticizer migration towards the matrix surface was observed in stored films. Films resulted stable till aw = 0.7 and due to their selective gaseous permeability they are useful to package products susceptible to oxidation or to control vegetable respiration and senescence. 相似文献
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Seongcheol Choi Carson Cheung Olivia A. Graeve 《Journal of the American Ceramic Society》2021,104(7):3030-3041
We describe the manufacturing of a solid-oxide fuel cell anode of NiO−8 mol.% Y2O3-stabilized ZrO2 with micro-scale continuous linear pores (CLPs) and nano-scale interparticle pore structures, achieved through thermal decomposition of unidirectional amorphous carbon fibers. The CLP structure prepared by this sacrificial templating method is characterized by its controllable uniform size, a tortuosity (ie, uniformity) of 1.003, and a coefficient of variation of 0.59. These highly regular CLPs are expected to minimize Knudsen diffusion, resulting in enhanced mass transport of hydrogen gas at the active sites, known as triple-phase boundary sites. Simulations using the Lattice Boltzmann Method (LBM) were used to determine the mass transport in the systems. An optimum diameter of 3 µm and an interparticle pore size of 185 nm was shown to maximize the acceleration of mass transport of H2 and maintain the number of TPB sites to minimize concentration overpotential. Thus, the proposed porous design can increase the energy efficiency of a solid-oxide fuel cell primarily by reducing the concentration overpotential. 相似文献
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Susanne Maria Hilda Haindl Olivia Doppleb Lucas Förster Sophia Wraage Annette Reiche 《化学,工程师,技术》2020,92(8):1109-1121
Protein adsorption is usually regarded as the main reason for filter fouling in sterile filtration of protein formulations. To achieve a better insight into this phenomenon, protein adsorption was studied during filtration of stabilized bovine serum albumin (BSA) and γ-globulin formulations through 0.2-µm microfilter membranes by inverse liquid chromatography (ILC). Adsorption processes can be studied with this method by measurement of breakthrough curves. The change of the concentration in the fluid phase is measured with high accuracy by an inline UV-detector. 相似文献
56.
María Virtudes Céspedes Olivia Cano-Garrido Patricia Álamo Rita Sala Alberto Gallardo Naroa Serna Aïda Falgàs Eric Voltà-Durán Isolda Casanova Alejandro Sánchez-Chardi Hèctor López-Laguna Laura Sánchez-García Julieta M. Sánchez Ugutz Unzueta Esther Vázquez Ramón Mangues Antonio Villaverde 《Advanced materials (Deerfield Beach, Fla.)》2020,32(7):1907348
Functional amyloids produced in bacteria as nanoscale inclusion bodies are intriguing but poorly explored protein materials with wide therapeutic potential. Since they release functional polypeptides under physiological conditions, these materials can be potentially tailored as mimetic of secretory granules for slow systemic delivery of smart protein drugs. To explore this possibility, bacterial inclusion bodies formed by a self-assembled, tumor-targeted Pseudomonas exotoxin (PE24) are administered subcutaneously in mouse models of human metastatic colorectal cancer, for sustained secretion of tumor-targeted therapeutic nanoparticles. These proteins are functionalized with a peptidic ligand of CXCR4, a chemokine receptor overexpressed in metastatic cancer stem cells that confers high selective cytotoxicity in vitro and in vivo. In the mouse models of human colorectal cancer, time-deferred anticancer activity is detected after the subcutaneous deposition of 500 µg of PE24-based amyloids, which promotes a dramatic arrest of tumor growth in the absence of side toxicity. In addition, long-term prevention of lymphatic, hematogenous, and peritoneal metastases is achieved. These results reveal the biomedical potential and versatility of bacterial inclusion bodies as novel tunable secretory materials usable in delivery, and they also instruct how therapeutic proteins, even with high functional and structural complexity, can be packaged in this convenient format. 相似文献
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Gadelrab Olivia Elmahgary Maryam G. Mahran Abdelrahman M. Ganoub Moustafa Abdellatif Sameh O. 《Journal of Materials Science: Materials in Electronics》2022,33(15):12053-12061
Journal of Materials Science: Materials in Electronics - Various solar cell architectures and materials are currently studied, seeking enhanced photon management mechanisms. Herein, we provide an... 相似文献
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Induction of plant chemical defenses in response to insect feeding may be localized to the site of damage or expressed systemically, mediated by signal transduction throughout the plant. Such systemic induction processes have been widely investigated in plants with single stems, but rarely in clonal plants comprised of multiple ramets with vascular connections. For a clonal tree species such as trembling aspen (Populus tremuloides Michx), integration of induced defense within clones could be adaptive, as clones are spatially extensive and susceptible to outbreak herbivores. We used pairs of aspen saplings with shared roots, replicated from three genotypes, to determine whether defense-induction signals are communicated within clones. One ramet in each pair was subjected to a damage treatment (feeding by Lymantria dispar, followed by mechanical damage), and subsequent changes in leaf defensive chemistry were measured in both ramets. Responses to damage varied by defense type: condensed tannins (CTs) increased in damaged ramets but not in connected undamaged ramets, whereas salicinoid phenolic glycosides (SPGs) were not induced in any ramets. Genotypes varied in their levels of CTs, but not in their levels of SPGs, and responded similarly to damage treatment. These results suggest that, even with both vascular and volatile information available, young aspen ramets do not induce defenses based on signals or metabolites from other ramets. Thus, unlike other clonal plant species, aspen do not appear to coordinate defense induction within clones. Lack of coordinated early induction in aspen may be related to the function of CTs in tolerance, rather than resistance. 相似文献