scholarly journals Shape Correction Factor for Drying Shrinkage in a Concrete Cross-Section

CONCREEP 10 ◽  
2015 ◽  
Author(s):  
N. Reybrouck ◽  
P. Criel ◽  
R. Caspeele ◽  
L. Taerwe
Keyword(s):  
Cross Section ◽  
Correction Factor ◽  
Drying Shrinkage ◽  
Shape Correction

Effective, Shortened Drying of Agar-Gelcasting Al2O3 Tube Through Immersing in Acetone

2021 ◽  
Author(s):  
Ramnaree Kaemkit ◽  
Supawan Vichaphund ◽  
Anukorn Phureungrat ◽  
Methee Promsawat ◽  
Suksawat Sirijarukul ◽  
...  
Keyword(s):  
Cross Section ◽  
Concentration Gradient ◽  
Water Concentration ◽  
Drying Shrinkage ◽  
The Other ◽  
Air Drying ◽  
Al2o3 Tube ◽  
Acetone Water ◽  
Porous Microstructure ◽  
Glass Tubes

Abstract A liquid drying agent, i.e. acetone, was employed for allowing the faster drying of Al2O3 tubes fabricated by agar gelcasting than the conventional air drying. The mixture of Al2O3 slurry and agar solution was separately prepared and then mixed prior to molding out of a set of warmed glass tubes. After the mixture transformed into gelled tube, the gelled tube was demolded and then immersed in acetone at different periods of time from 0 to 50 h. The immersed periods of 50 h led to the acetone replacement for water being inside of the gelling tube by 74 wt.% and then shortened the drying period to be 25 min. On the other hand, the conventional air drying spent 420 min drying completely. After drying, the immersed tubes possessed spherical cross section; whereas, no immersed tubes showed the deformation of cross section. The shortened drying was in line with the smaller drying shrinkage (4.7%), broader pore-size distribution and higher porous microstructure, comparing to the conventional air drying. The mechanism of acetone replacement for water was attributed to the acetone-water concentration gradient creating their inter-diffusion.

Application of Thermal Sensors for Determination of Mass Flow Rate and Velocity of Flow in Pipes of Hermetic Systems

2019 ◽  
Vol 826 ◽  
pp. 117-124
Author(s):  
Yurii Baidak ◽  
Iryna Vereitina
Keyword(s):  
Temperature Distribution ◽  
Mass Flow Rate ◽  
Cross Section ◽  
Correction Factor ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Sensors ◽  
Pipe Surface ◽  
Pipe Cross Section

The paper relates to the field of measuring technologies and deals with the enhancement of thermoconvective method when it is applied for the experimental determination of such hydrodynamics indicators as mass flow rate and velocity of flow by their indirect parameters - capacity of the heater and the temperatures obtained from two thermal sensors, provided that they are located on the hermetic piping system surface. The issue of determination of correction factor on heterogeneity of liquid temperature distribution in the pipe cross section depending on pipe diameter and fluid movement velocity was clarified. According to the results of numerical calculations, the dependencies of temperature gradient on the pipe surface and the correction factor on the heterogeneity of the temperature distribution along the pipe cross-section under the heater in the function of the velocity of flow in pipes of different diameters are plotted. These dependencies specify the thermal method of studying the fluid flow in the pipes, simplify the experiment conduction, are useful in processing of the obtained results and can be applied in measuring engineering.

scholarly journals Using cell cross-section dimensions and digital image correlation to evaluate drying shrinkage and collapse in Eucalyptus nitens wood

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6149-6164
Author(s):  
Alan Dickson ◽  
Bernard Dawson
Keyword(s):  
Digital Image Correlation ◽  
Cross Section ◽  
Digital Image ◽  
Laser Scanning ◽  
Drying Shrinkage ◽  
Laser Scanning Microscopy ◽  
Image Correlation ◽  
Confocal Laser ◽  
Eucalyptus Nitens ◽  
Vessel Elements

An approach combining maps of wood morphology and digital image correlation was developed to investigate the drying of Eucalyptus nitens wood. Maps of morphological features (vessel and ray distribution) and cell cross-section dimensions were acquired by confocal laser scanning microscopy. Shrinkage maps were generated using digital image correlation. There were statistically significant correlations between shrinkage/collapse and wood morphology at two levels. Firstly, there were positional relationships, with for example, both radial and tangential shrinkage increasing with increasing distance from vessel elements. Secondly, there were dimensional relationships, such as, cells with large perimeters (relative to their wall thickness) on average showing greater shrinkage. Generally, the positional relationships dominated the dimensional relationships. Detailed analysis over large areas allows for a fuller analysis of the interrelationship between wood morphology and drying shrinkage and collapse.

Inner Bremsstrahlung Accompanying the Non-Unique First Forbidden β-Decay of 141Ce

1993 ◽  
Vol 48 (11) ◽  
pp. 1115-1118 ◽  
Author(s):  
E. I. Khalil
Keyword(s):  
Correction Factor ◽  
Single Channel ◽  
Experimental Results ◽  
The Other ◽  
Β Decay ◽  
Inner Bremsstrahlung ◽  
Shape Correction ◽  
Peeling Off

Abstract The inner Bremsstrahlung (I.B.) spectrum accompanying the β-decay of 141Ce (non-unique first forbidden β-transition) was measured using a single channel scintillation spectrometer. The measured I.B. was analyzed by the variable width peeling-off method. This analyzed and corrected I.B. was compared with those calculated according to the original theories of Knipp and Uhlenbeck as well as of Bloch (KUB), the coulomb corrected theories of Lewis and Ford and of Nilsson, and according to detour-transition calculations of the Ford and Martin theory. Ths shape correction factor suggested by Konopinski and Uhlenbeck on the Fermi β-decay theory was applied to the calculated I.B. based on Nilsson's theory (modified KUB theory). The experimental results are in better agreement with the modified KUB theory than the other theories.

scholarly journals Utilization of Completely Recycled Fine Aggregate for Preparation of Lightweight Concrete Partition Panels

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Yibo Yang ◽  
Baixi Chen ◽  
Weizhen Zeng ◽  
Yanjun Li ◽  
Qiaohui Chen ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Economic Analysis ◽  
Pore Structure ◽  
Cross Section ◽  
Lightweight Concrete ◽  
Drying Shrinkage ◽  
Fine Aggregate ◽  
Curing Process ◽  
Recycled Fine Aggregate ◽  
The Cost

AbstractTo reduce the cost of lightweight concrete (LWC) partition panels and to address recycling concrete waste, this work utilized completely recycled fine aggregate (CRFA) to replace the natural fine aggregate and ceramsite in the preparation of LWC and LWC partition panels. To this end, an autoclave-free curing process and an air-entraining agent were used to prepare the CRFA-LWC. The workability, compressive strength, drying shrinkage, and pore structure of the CRFA-LWC and the performance of the CRFA-LWC partition panels were then investigated. The results show that the optimal ratio of the CRFA to the cement is 2.2 for the lightweight concrete, and the optimal panel cross section is a rounded rectangular one. All the pores in the CRFA-LWC have a diameter of smaller than 0.17 mm, and the diameter of 89% of them is less than 0.05 mm. In order to satisfy the drying shrinkage requirements stipulated by Chinese code JC/T 169-2016, the CRFA-LWC should be cured for at least 10 days. The economic analysis concludes that the material cost of CRFA-LWC is 40% lower than that of the autoclaved ceramsite concrete. In addition, utilizing CRFA in lightweight concrete can ease the shortage of natural aggregate.

scholarly journals Charge Exchange Collisions Involving Multielectron Atoms (Lithium and Sodium)

1968 ◽  
Vol 21 (6) ◽  
pp. 793 ◽  
Author(s):  
JG Lodge ◽  
RM May
Keyword(s):  
Excited State ◽  
Cross Section ◽  
Charge Exchange ◽  
Correction Factor ◽  
Ground State ◽  
Hydrogen Atoms ◽  
Sodium Atoms ◽  
The Cross ◽  
Multielectron Atoms

The cross section for forming both ground state and excited state hydrogen atoms by charge exchange between protons and lithium or sodium atoms is calculated. These calculations are performed using the Brinkman-Kramers approximation along with a multiplicative correction factor; the target lithium and sodium atoms are first described by simple "effective-Z" wavefunctions, and then the lithium case is treated more accurately both by including the inner electrons and by using a more accurate numerical lithium wavefunction.

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