Towards Tuning the Modality of Hierarchical Macro-Nanoporous Metals by Controlling the Dealloying Kinetics of Close-to-Eutectic Alloys

The governing equations of the flow field which is obtained when a thermoelastic rigid porous medium is struck head-one by a shock wave are developed using the multiphase approach. The one-dimensional version of these equations is solved numerically using a TVD-based numerical code. The numerical predictions are compared to experimental results and good to excellent agreements are obtained for different porous materials and a wide range of initial conditions.

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Combining experimental and simulation data of molecular processes via augmented Markov models

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1704803114 ◽

2017 ◽

Vol 114 (31) ◽

pp. 8265-8270 ◽

Cited By ~ 53

Author(s):

Simon Olsson ◽

Hao Wu ◽

Fabian Paul ◽

Cecilia Clementi ◽

Frank Noé

Keyword(s):

Force Field ◽

Structural Changes ◽

Markov Models ◽

Force Fields ◽

Divide And Conquer ◽

Simulation Data ◽

Wide Range ◽

Simulation And Experiment ◽

Kinetics Of

Accurate mechanistic description of structural changes in biomolecules is an increasingly important topic in structural and chemical biology. Markov models have emerged as a powerful way to approximate the molecular kinetics of large biomolecules while keeping full structural resolution in a divide-and-conquer fashion. However, the accuracy of these models is limited by that of the force fields used to generate the underlying molecular dynamics (MD) simulation data. Whereas the quality of classical MD force fields has improved significantly in recent years, remaining errors in the Boltzmann weights are still on the order of a few kT, which may lead to significant discrepancies when comparing to experimentally measured rates or state populations. Here we take the view that simulations using a sufficiently good force-field sample conformations that are valid but have inaccurate weights, yet these weights may be made accurate by incorporating experimental data a posteriori. To do so, we propose augmented Markov models (AMMs), an approach that combines concepts from probability theory and information theory to consistently treat systematic force-field error and statistical errors in simulation and experiment. Our results demonstrate that AMMs can reconcile conflicting results for protein mechanisms obtained by different force fields and correct for a wide range of stationary and dynamical observables even when only equilibrium measurements are incorporated into the estimation process. This approach constitutes a unique avenue to combine experiment and computation into integrative models of biomolecular structure and dynamics.

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Ordered Hierarchical Porous Materials: Towards Tunable Size- and Shape-Selective Microcavities in Nanoporous Channels

Angewandte Chemie International Edition ◽

10.1002/1521-3773(20000804)39:15<2702::aid-anie2702>3.0.co;2-f ◽

2000 ◽

Vol 39 (15) ◽

pp. 2702-2707 ◽

Cited By ~ 57

Author(s):

Yongsoon Shin ◽

Jun Liu ◽

Li-Qiong Wang ◽

Zimin Nie ◽

William D. Samuels ◽

...

Keyword(s):

Porous Materials ◽

Size And Shape ◽

Hierarchical Porous ◽

Shape Selective

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Non-Isothermal Crystallisation Kinetics of Polypropylene at High Cooling Rates and Comparison to the Continuous Two-Domain pvT Model

Polymers ◽

10.3390/polym12071515 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1515

Author(s):

Jonathan Alms ◽

Christian Hopmann ◽

Jian Wang ◽

Tobias Hohlweck

Keyword(s):

Injection Moulding ◽

Polymer Processing ◽

Nucleation And Growth ◽

Growth Theory ◽

Crystallisation Kinetics ◽

Cooling Rates ◽

Dsc Measurements ◽

Wide Range ◽

High Cooling Rates ◽

Kinetics Of

The modelling of the correlation between pressure, specific volume and temperature (pvT) of polymers is highly important for applications in the polymer processing of semi-crystalline thermoplastics, especially in injection moulding. In injection moulding, the polymer experiences a wide range of cooling rates, for example, 60 °C/min near the centre of the part and up to 3000 °C/min near the mould walls. The cooling rate has a high influence on the pvT behaviour, as was shown in the continuous two-domain pvT model (CTD). This work examined the Hoffman–Lauritzen nucleation and growth theory used in the modified Hammami model for extremely high cooling rates (up to 300,000 °C/min) by means of Flash differential scanning calorimeter (DSC) measurements. The results were compared to those of the empirical continuous two-domain pvT model. It is shown that the Hammami model is not suitable to predict the crystallisation kinetics of polypropylene at cooling rates above 600 °C/min, but that the continuous two-domain pvT model is well able to predict crystallisation temperatures at high cooling rates.

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Automated System for Kinetic Analysis of Particle Size Distributions for Pharmaceutically Relevant Systems

Journal of Analytical Methods in Chemistry ◽

10.1155/2014/810589 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8

Author(s):

John-Bruce D. Green ◽

Phillip W. Carter ◽

Yingqing Zhang ◽

Dipa Patel ◽

Priyanka Kotha ◽

...

Keyword(s):

Particle Size ◽

Clinical Importance ◽

Automated System ◽

Size Distributions ◽

Mixing Conditions ◽

Particle Size Distributions ◽

Complex Formulation ◽

Wide Range ◽

Key Variables ◽

Kinetics Of

Detailing the kinetics of particle formation for pharmaceutically relevant solutions is challenging, especially when considering the combination of formulations, containers, and timescales of clinical importance. This paper describes a method for using commercial software Automate with a stream-selector valve capable of sampling container solutions from within an environmental chamber. The tool was built to monitor changes in particle size distributions via instrumental particle counters but can be adapted to other solution-based sensors. The tool and methodology were demonstrated to be highly effective for measuring dynamic changes in emulsion globule distributions as a function of storage and mixing conditions important for parenteral nutrition. Higher levels of agitation induced the fastest growth of large globules (≥5 μm) while the gentler conditions actually showed a decrease in the number of these large globules. The same methodology recorded calcium phosphate precipitation kinetics as a function of [Ca2+] and pH. This automated system is readily adaptable to a wide range of pharmaceutically relevant systems where the particle size is expected to vary with time. This instrumentation can dramatically reduce the time and resources needed to probe complex formulation issues while providing new insights for monitoring the kinetics as a function of key variables.

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The Growth Kinetics of RhizoctoniasolaniAfter 1 MeV Electron Irradiation

KnE Life Sciences ◽

10.18502/kls.v7i1.10106 ◽

2022 ◽

Author(s):

Ulyana Bliznyuk ◽

Natalya Chulikova ◽

Anna Malyuga

Keyword(s):

Radial Growth ◽

Radiation Treatment ◽

Dose Range ◽

Black Scurf ◽

Phytopathogenic Fungus ◽

Complete Suppression ◽

Electron Radiation ◽

Bacterial Diseases ◽

Wide Range ◽

Kinetics Of

Crops, especially potatoes, are prone to a wide range of fungal, viral and bacterial diseases, including black scurf caused by Rhizoctoniasolani. This study focused on the radiation treatment of the phytopathogenic fungus RhizoctoniasolaniKuhn, grown from sclerotium irradiated with 1 MeV electrons in the dose range from 20 to 4500 Gy. The doses absorbed by the sclerotia were determined using computer simulation. The growth of the fungus samples was monitored after 24, 48, 72, and 96 hours from the time of seeding. It was found that the dependence of the radial growth velocity of R. solani on the time after irradiation with doses ranging from 20to 1800 Gywas nonlinear. Irradiation at a dose over 4500 Gyled to complete suppression of the germination of R. solani sclerotia. Keywords: radiation treatment, electron radiation, radiation dose, sclerotia of Rhizoctoniasolani, Kuhn, radial velocity of growth

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An 112 Days Experiment on Dietary Cadmium Retention in Hepatopancreas in Adult Cantareus aspersus Snails

Revista de Chimie ◽

10.37358/rc.19.8.7431 ◽

2019 ◽

Vol 70 (8) ◽

pp. 2803-2804

Author(s):

George A. Draghici ◽

Cristina A. Dehelean ◽

Iulia Pinzaru ◽

Despina M. Bordean ◽

Georgeta Pop ◽

...

Keyword(s):

Absorption Spectrometry ◽

Dry Weight ◽

Land Snails ◽

Dependent Manner ◽

Flame Atomic Absorption ◽

Wide Range ◽

Cantareus Aspersus ◽

Ecotoxicological Model ◽

Dietary Cadmium ◽

Kinetics Of

Cadmium is very hazardous pollutant with massive impact on aspects of everyday life. Little knowledge exists on kinetics of dietary cadmium retention in Cantareus aspersus for durations above three months although this species of land snails serves as excellent ecotoxicological model for studying cadmium hazard. Here was used a continuous 112-day exposure study design, in which test snails were exposed to a wide range of dietary cadmium levels, including human- and environmentally-relevant levels. Using Flame Atomic Absorption Spectrometry, cadmium levels in the hepatopancreas were found to increase significantly, and in dose-dependent manner starting from a dietary cadmium dose of 0.2 mg/kg dry weight. The results of the present study render the hepatopancreas of mature snails, C. aspersus, as excellent endpoints for assessing Cd toxicity over a broad range of concentrations. Hence, this species of land snails can be reliably used for both active and passive biomonitoring of environmental cadmium pollution.

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