A study on the sensitivity of the measurement of liquid density at different scattering angles using a gamma scattering technique

2021 ◽  
pp. 109897
Author(s):  
Huynh Dinh Chuong ◽  
Nguyen Thi Kim Anh ◽  
Truong Thanh Sang ◽  
Le Thi Ngoc Trang ◽  
Nguyen Thi Truc Linh ◽  
...  
Keyword(s):  
Liquid Density ◽  
Scattering Technique

scholarly journals Investigation of the liquid density using Gamma scattering technique

2017 ◽  
Vol 1 (T1) ◽  
pp. 106-113
Author(s):  
Kien Thach Trung Vo ◽  
Tam Duc Hoang ◽  
Nguyen Hoang Vo ◽  
Chuong Dinh Huynh ◽  
Thanh Thien Tran ◽  
...  
Keyword(s):  
Multiple Scattering ◽  
Density Measurement ◽  
Single Scattering ◽  
Photon Beam ◽  
Scattered Photon ◽  
Liquid Density ◽  
Scattering Angle ◽  
Testing Sample ◽  
Scattering Technique

In this work, a gamma scattering technique using 137Cs (5mCi) source with the NaI(Tl) detector is arranged to record the scattered photon beam at scattering angle of 1200 for investigating the liquid density. We used standard liquid such as water, H2SO4, HCl, glycerol, HNO3, ethanol and A92 petrol to fit the single scattering peak, multiple scattering, and total counts versus standard liquid densities. The interpolating of the single scattering peak, multiple scattering, and total counts of the testing sample at scattering angle of 1200 is 0.702 g.cm-3, 0.783 g.cm-3, and 0.747 g.cm-3, respectively. The discrepancy of the experiment and true testing density is about 8 %, 3 %, and 2 %, respectively. The result shows that multiple scattering or total counts can be used to propose the density measurement.

QUBEKit: Automating the Derivation of Force Field Parameters from Quantum Mechanics

2019 ◽  
Author(s):  
Joshua Horton ◽  
Alice Allen ◽  
Leela Dodda ◽  
Daniel Cole
Keyword(s):  
Quantum Mechanics ◽  
Force Field ◽  
Organic Molecules ◽  
Force Fields ◽  
Liquid Density ◽  
Small Organic Molecules ◽  
Automated Generation ◽  
Energy Of Hydration ◽  
Novel Method ◽  
Force Field Parameters

<div><div><div><p>Modern molecular mechanics force fields are widely used for modelling the dynamics and interactions of small organic molecules using libraries of transferable force field parameters. For molecules outside the training set, parameters may be missing or inaccurate, and in these cases, it may be preferable to derive molecule-specific parameters. Here we present an intuitive parameter derivation toolkit, QUBEKit (QUantum mechanical BEspoke Kit), which enables the automated generation of system-specific small molecule force field parameters directly from quantum mechanics. QUBEKit is written in python and combines the latest QM parameter derivation methodologies with a novel method for deriving the positions and charges of off-center virtual sites. As a proof of concept, we have re-derived a complete set of parameters for 109 small organic molecules, and assessed the accuracy by comparing computed liquid properties with experiment. QUBEKit gives highly competitive results when compared to standard transferable force fields, with mean unsigned errors of 0.024 g/cm3, 0.79 kcal/mol and 1.17 kcal/mol for the liquid density, heat of vaporization and free energy of hydration respectively. This indicates that the derived parameters are suitable for molecular modelling applications, including computer-aided drug design.</p></div></div></div>

QUBEKit: Automating the Derivation of Force Field Parameters from Quantum Mechanics

2019 ◽  
Author(s):  
Joshua Horton ◽  
Alice Allen ◽  
Leela Dodda ◽  
Daniel Cole
Keyword(s):  
Quantum Mechanics ◽  
Force Field ◽  
Organic Molecules ◽  
Force Fields ◽  
Liquid Density ◽  
Small Organic Molecules ◽  
Automated Generation ◽  
Energy Of Hydration ◽  
Novel Method ◽  
Force Field Parameters

<div><div><div><p>Modern molecular mechanics force fields are widely used for modelling the dynamics and interactions of small organic molecules using libraries of transferable force field parameters. For molecules outside the training set, parameters may be missing or inaccurate, and in these cases, it may be preferable to derive molecule-specific parameters. Here we present an intuitive parameter derivation toolkit, QUBEKit (QUantum mechanical BEspoke Kit), which enables the automated generation of system-specific small molecule force field parameters directly from quantum mechanics. QUBEKit is written in python and combines the latest QM parameter derivation methodologies with a novel method for deriving the positions and charges of off-center virtual sites. As a proof of concept, we have re-derived a complete set of parameters for 109 small organic molecules, and assessed the accuracy by comparing computed liquid properties with experiment. QUBEKit gives highly competitive results when compared to standard transferable force fields, with mean unsigned errors of 0.024 g/cm3, 0.79 kcal/mol and 1.17 kcal/mol for the liquid density, heat of vaporization and free energy of hydration respectively. This indicates that the derived parameters are suitable for molecular modelling applications, including computer-aided drug design.</p></div></div></div>

scholarly journals From Femtoseconds to Hours–Measuring Dynamics over 18 Orders of Magnitude with Coherent X-rays

2021 ◽  
Vol 11 (13) ◽  
pp. 6179
Author(s):  
Felix Lehmkühler ◽  
Wojciech Roseker ◽  
Gerhard Grübel
Keyword(s):  
Time Scales ◽  
Free Electron Laser ◽  
Photon Correlation Spectroscopy ◽  
Signal To Noise Ratio ◽  
Coherent Scattering ◽  
Correlation Spectroscopy ◽  
X Rays ◽  
Photon Correlation ◽  
X Ray ◽  
Scattering Technique

X-ray photon correlation spectroscopy (XPCS) enables the study of sample dynamics between micrometer and atomic length scales. As a coherent scattering technique, it benefits from the increased brilliance of the next-generation synchrotron radiation and Free-Electron Laser (FEL) sources. In this article, we will introduce the XPCS concepts and review the latest developments of XPCS with special attention on the extension of accessible time scales to sub-μs and the application of XPCS at FELs. Furthermore, we will discuss future opportunities of XPCS and the related technique X-ray speckle visibility spectroscopy (XSVS) at new X-ray sources. Due to its particular signal-to-noise ratio, the time scales accessible by XPCS scale with the square of the coherent flux, allowing to dramatically extend its applications. This will soon enable studies over more than 18 orders of magnitude in time by XPCS and XSVS.

scholarly journals Surface Tension and Density of Liquid Hot Work Tool Steel W360 by voestalpine BÖHLER Edelstahl GmbH & Co KG Measured with an Electromagnetic Levitation Apparatus

2020 ◽  
Vol 42 (2) ◽  
Author(s):  
Thomas Leitner ◽  
Anna Werkovits ◽  
Siegfried Kleber ◽  
Gernot Pottlacher
Keyword(s):  
Surface Tension ◽  
Temperature Dependence ◽  
Linear Model ◽  
Tool Steel ◽  
Pure Iron ◽  
Electromagnetic Levitation ◽  
Liquid Density ◽  
Hot Work Tool Steel ◽  
Significant Difference ◽  
Main Component

AbstractW360 is a hot work tool steel produced by voestalpine BÖHLER Edelstahl GmbH & Co KG, a special steel producer located in Styria, Austria. Surface tension and density of liquid W360 were studied as a function of temperature in a non-contact, containerless fashion using the oscillating drop method inside an electromagnetic levitation setup. For both, surface tension and density, a linear model was adapted to present the temperature dependence of these measures, including values for the uncertainties of the fit parameters found. The data obtained are compared to pure iron (with 91 wt% the main component of W360), showing an overlap for the liquid density while there is a significant difference in surface tension (− 5.8 % at the melting temperature of pure iron of 1811 K).

Sign in / Sign up

Export Citation Format

Share Document