Investigating the Relationship between Microstructural Properties and Geomechanical Characteristics, Iranian Reservoir

This paper addresses the regeneration of the sulphur capture ability of FB spent SO2 sorbent particles by steam hydration. The process was characterized in terms of hydration degree, particle sulphation pattern, development of accessible porosity and extent of particle fragmentation. Steam reactivation experiments were carried out in a lab-scale fluidized bed reactor at 250°C for 10 and 30 minutes, and 3h. The sorbent particle size range was 0.4–0.6mm, and the bed was fluidized at 0.2m/s with a steam-N2 mixture. The effectiveness of sorbent reactivation was assessed by reinjecting the reactivated material into the FB reactor (fluidized at 0.8m/s) operated at 850°C under simulated desulphurization conditions (the fluidizing gas consisted of a SO2-O2-N2 mixture), and following the degree of calcium conversion and the attrition rate along with resulphation. The experimental results indicated that steam reactivation is effective in renewing the SO2 uptake ability of the exhausted sorbent particles. Moreover steam reactivation induces, in the samples investigated, a strong sulphur redistribution throughout the particle cross-section, which contributes to the enhancement of the sulphur capture ability of the reactivated sorbent.

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Lamination Process to Obtain Structure with Tailored Residual Stress Distribution

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.333.27 ◽

2007 ◽

Vol 333 ◽

pp. 27-38 ◽

Cited By ~ 2

Author(s):

Goffredo de Portu ◽

Lorenzo Micele

Keyword(s):

Residual Stresses ◽

Tape Casting ◽

Ceramic Composites ◽

Residual Stress Distribution ◽

Thin Layers ◽

Microstructural Properties ◽

Laminated Structure ◽

Physical Chemical ◽

Lamination Process ◽

The Relationship

In this paper a method to produce laminated ceramic composites containing residual stresses is described. The method consist in superimposing thin layers obtained by tape casting, their worm-pressing and sintering. Detailed information on the process and on the slurry compositions are reported. The reasons why laminated structure can exhibit improved performances are also illustrated. The model on which a multilayer composite, containing residual stresses, can be designed is briefly illustrated. The relationship among the physical, chemical and microstructural properties of the different layers, necessary to stimulate the residual stresses outlined.

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Right fronto-parietal networks mediate the neurocognitive benefits of enriched environments.

10.1101/2021.09.01.458571 ◽

2021 ◽

Author(s):

Meadhbh B Brosnan ◽

Nir Shalev ◽

Jivesh Ramduny ◽

Stamatios Sotiropoulos ◽

Magdalena Chechlacz

Keyword(s):

White Matter ◽

Executive Control ◽

Grey Matter ◽

Microstructural Properties ◽

Brain Health ◽

Superior Longitudinal Fasciculus ◽

Age Related ◽

Enriched Environments ◽

The Right ◽

The Relationship

Exposure to enriched environments (EE) throughout a lifetime, providing so called reserve, protects against cognitive decline in later years. It has been hypothesised that high levels of alertness necessitated by EE might strengthen the right fronto-parietal networks (FPN) to facilitate this neurocognitive resilience. We have previously shown that EE offset age-related deficits in selective attention by preserving grey matter within right fronto-parietal regions. Here, using neurite orientation dispersion and density imaging (NODDI), we examined the relationship between EE, microstructural properties of fronto-parietal white matter association pathways (three branches of the superior longitudinal fasciculus, SLF), structural brain health (atrophy), and attention (alertness, orienting and executive control) in a group of older adults. We show that EE is associated with a lower orientation dispersion index (ODI) within the right SLF1 which in turn mediates the relationship between EE and alertness, as well as grey- and white-matter atrophy. This suggests that EE may induce white matter plasticity (and prevent age-related dispersion of axons) within the right FPN to facilitate the preservation of neurocognitive health in later years.

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Exploring the Relationship between Gray and White Matter in Healthy Adults: A Hybrid Research of Cortical Reconstruction and Tractography

BioMed Research International ◽

10.1155/2021/6628506 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Yongxiang Zhao ◽

Qianqian Li ◽

Jiachen Du ◽

Hongjian He ◽

Peipeng Liang ◽

...

Keyword(s):

White Matter ◽

Brain Regions ◽

Healthy Adults ◽

Microstructural Properties ◽

Diffusion Spectrum Imaging ◽

Diffusion Parameters ◽

Spectrum Imaging ◽

Cortical Morphology ◽

The Relationship ◽

The Brain

The gray matter (GM) and white matter (WM) are structurally and functionally related in the human brain. Among the numerous neuroimaging studies, yet only a few have investigated these two structures in the same sample. So, there is limited and inconsistent information about how they are correlated in the brain of healthy adults. In this study, we combined cortical reconstruction with diffusion spectrum imaging (DSI) tractography to investigate the relationship between cortical morphology and microstructural properties of major WM tracts in 163 healthy young adults. The results showed that cortical thickness (CTh) was positively correlated with the coherent tract-wise fractional anisotropy (FA) value, and the correlation was stronger in the dorsal areas than in the ventral areas. For other diffusion parameters, CTh was positively correlated with axial diffusivity (AD) of coherent fibers in the frontal areas and negatively correlated with radial diffusivity (RD) of coherent fibers in the dorsal areas. These findings suggest that the correlation between GM and WM is inhomogeneity and could be interpreted with different mechanisms in different brain regions. We hope our research could provide new insights into the studies of diseases in which the GM and WM are both affected.

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Effect of Controlled Rate Freezing on the Microstructural Properties of Poly (L-lactic Acid) Scaffolds

Volume 2: Biomedical and Biotechnology ◽

10.1115/imece2012-87558 ◽

2012 ◽

Author(s):

Harish Chinnasami ◽

George Idicula ◽

Daniel Hayes ◽

Ram Devireddy

Keyword(s):

Lactic Acid ◽

Microstructural Properties ◽

Dioxane Solution ◽

Thermally Induced Phase Separation ◽

Sem Images ◽

Cooling Rates ◽

Thermally Induced ◽

Freeze Dried ◽

Compressive Testing ◽

The Relationship

Bio-degradable poly (l-lactic acid) (PLLA) scaffolds were prepared by using thermally induced phase separation (TIPS) method. A solution of PLLA-Dioxane was formed by dissolving PLLA in dehydrated 1,4-Dioxane at three wt/vol percentages, specifically 3, 7 and 10%. This PLLA-Dioxane solution was then frozen in borosilicate glass vials (5mL) at three cooling rates (1, 10 and 40 °C/min) in a commercially available controlled rate freezer (CRF). The frozen solution was freeze-dried to sublimate the dioxane. The microstructural properties of the resulting PLLA scaffolds were determined utilizing Scanning Electron Microscopy (SEM) images and uniaxial compressive testing. The relationship between the wt/vol ratio of PLLA and Dioxane and the imposed cooling rates on the structural properties of PLLA scaffolds was determined.

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Interstellar gas in the central region of the Galaxy

Symposium - International Astronomical Union ◽

10.1017/s0074180900101032 ◽

1967 ◽

Vol 31 ◽

pp. 239-251 ◽

Cited By ~ 3

Author(s):

F. J. Kerr

Keyword(s):

Central Region ◽

Galactic Plane ◽

Neutral Hydrogen ◽

Continuum Emission ◽

Galactic Centre ◽

Interstellar Gas ◽

Hydrogen Recombination ◽

The Galaxy ◽

Centre Region ◽

The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

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The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽

10.1017/s0094837300025707 ◽

1980 ◽

Vol 6 (02) ◽

pp. 146-160 ◽

Cited By ~ 29

Author(s):

William A. Oliver

Keyword(s):

Critical Points ◽

Scleractinian Corals ◽

Convincing Evidence ◽

Early Triassic ◽

Rugose Corals ◽

History Of ◽

The Subject ◽

Relationship Of ◽

The Relationship ◽

Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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Choosing a Markov blanket

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002632 ◽

2020 ◽

Vol 43 ◽

Author(s):

Thomas Parr

Keyword(s):

Markov Blanket ◽

Target Article ◽

The Relationship

Abstract This commentary focuses upon the relationship between two themes in the target article: the ways in which a Markov blanket may be defined and the role of precision and salience in mediating the interactions between what is internal and external to a system. These each rest upon the different perspectives we might take while “choosing” a Markov blanket.

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Tinkering with cognitive gadgets: Cultural evolutionary psychology meets active inference

Behavioral and Brain Sciences ◽

10.1017/s0140525x19001018 ◽

2019 ◽

Vol 42 ◽

Author(s):

Paul Benjamin Badcock ◽

Axel Constant ◽

Maxwell James Désormeau Ramstead

Keyword(s):

Evolutionary Psychology ◽

Research Program ◽

Active Inference ◽

Innovative Research ◽

Cognitive Faculties ◽

Cultural Evolutionary ◽

The Relationship

Abstract Cognitive Gadgets offers a new, convincing perspective on the origins of our distinctive cognitive faculties, coupled with a clear, innovative research program. Although we broadly endorse Heyes’ ideas, we raise some concerns about her characterisation of evolutionary psychology and the relationship between biology and culture, before discussing the potential fruits of examining cognitive gadgets through the lens of active inference.

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Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068291 ◽

1970 ◽

Vol 28 ◽

pp. 260-261

Author(s):

Robert M. Glaeser

Keyword(s):

High Resolution ◽

Particle Flux ◽

Unit Area ◽

Signal To Noise ◽

Resolution Image ◽

High Resolution Image ◽

Pass Through ◽

Counting Statistics ◽

The Relationship ◽

Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

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