scholarly journals Modelling the Kinetics of Elements Release from a Zeolitic-Rich Tuff

Environments ◽  
2020 ◽  
Vol 7 (6) ◽  
pp. 41
Author(s):  
Eleonora Grilli ◽  
Antonio Ganga ◽  
Stefano Salvestrini
Keyword(s):  
Power Function ◽  
Empirical Equation ◽  
Acid Solutions ◽  
Zeolite Framework ◽  
Release Process ◽  
Weathering Processes ◽  
Second Stage ◽  
Third Stage ◽  
Elovich Equation ◽  
Kinetics Of

The present investigation aims at modeling the kinetics of elements (Fe, Mg, K, Ca, Na, Al, and Si) release from zeolitic-rich Phlegraean Yellow Tuff weathered by tannic acid solutions at different concentration. Three equations were tested—power function, the Weber–Morris model, and the Elovich equation. Power function was revealed to be an excellent empirical equation well fitted to the experimental data. Its numerical parameters were suitable predictive tools, highlighting both the intensity and modality of weathering processes. By paralleling the dissolution rates, it was possible to allow rock-sources from which elements were released during three distinct weathering stages—(i) the first stage was dominated by biotite and amorphous weathering, (ii) the second stage also started with the breakdown of zeolite framework; and (iii) in the third stage, the whole of weathering/release process approached a steady state. Finally, these outcomes may be used to forecast the pedogenic/nutritional potential of zeolitic-rich tuffs as pedotechnical matrices in restoration design.

A Model for Solar Photocatalytic Mineralization

2011 ◽  
Vol 133 (3) ◽  
Author(s):  
Franck Correia ◽  
Vincent Goetz ◽  
Gaël Plantard ◽  
Daniel Sacco
Keyword(s):  
Organic Pollutant ◽  
Weather Conditions ◽  
Second Stage ◽  
Third Stage ◽  
Different Dimensions ◽  
Set Up ◽  
Artificial Uv ◽  
Semi Empirical ◽  
Kinetics Of ◽  
Adjustment Of Parameters

Modeling the mineralization of an organic pollutant was studied using a slurry of TiO2 powder. 2-4 dichlorophenol was chosen as the target molecule. In a first stage, a study was carried out, on the basis of a semi-empirical approach in order to define the optimal concentration of the catalyst. In a second stage, a series of photocatalytic mineralization was performed with a laboratory set-up using an artificial UV source. The parameters involved in the kinetics of mineralization were identified by a comparison of results obtained by simulations and experiments at constant but different levels of irradiation. In a third stage, the robustness and suitability of the model were tested with experiments carried out with an experimental solar set-up with different dimensions. No supplementary adjustment of parameters was needed to simulate the experiments performed under unsteady irradiation. Finally, the model is used to illustrate the great variation in treatment capability of a solar photocatalytic process depending on the weather conditions and, more particularly, the seasonal variations in UV irradiation.

Soot-Ozone Reaction Kinetics: Spectroscopic and Gravimetric Studies

1988 ◽  
Vol 42 (8) ◽  
pp. 1473-1482 ◽  
Author(s):  
D. M. Smith ◽  
W. F. Welch ◽  
J. A. Jassim ◽  
A. R. Chughtai ◽  
D. H. Stedman
Keyword(s):  
Species Differences ◽  
Initial Rate ◽  
Flow Conditions ◽  
Concentration Data ◽  
First Order ◽  
Second Stage ◽  
Elovich Equation ◽  
Static Conditions ◽  
Kinetics Of ◽  
Equivalent Conditions

Studies on the kinetics of soot-O3 reactions, at various soot and ozone concentrations, have been conducted under flow conditions with ozone ranging from 50 to 15,000 ppm and soot from 2 to 350 mg. At lower concentrations, the initial rates of CO2 and CO formation are found to be half order with respect to soot and first order with respect to ozone. At higher concentrations, CO2 formation exhibits a more complex pattern. The initial rate for the formation of CO2 for a first stage is half order with respect to soot and 1.5 order with respect to O3, while the second stage is zero order in both species. Differences between data at higher and lower concentrations are discussed, and mechanisms for the formation of CO2 CO, and carboxylics during ozonation are suggested. Mass balance calculations on low concentration data reveal that only a small portion of the ozone is used to produce CO2, CO, H2O, and carboxylic species, most of it being decomposed catalytically over soot. At higher concentrations of O3 the rate of formation of carboxylic functionalities during the hexane soot-ozone reaction under static conditions has been examined. The initial rate, as determined by the Elovich equation, suggests that the soot-ozone reaction is nearly 6 times faster under equivalent conditions than the sool-NO2/N2O4 reaction reported earlier from this laboratory.

The Coherence of Mary Barton: Romance, Realism, and Utopia

2015 ◽  
Vol 5 (3) ◽  
pp. 185-200
Author(s):  
Robert Z. Birdwell
Keyword(s):  
Thomas Carlyle ◽  
The Novel ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Three Stages ◽  
Mode Of Production

Critics have argued that Elizabeth Gaskell's first novel, Mary Barton (1848), is split by a conflict between the modes of realism and romance. But the conflict does not render the novel incoherent, because Gaskell surpasses both modes through a utopian narrative that breaks with the conflict of form and gives coherence to the whole novel. Gaskell not only depicts what Thomas Carlyle called the ‘Condition of England’ in her work but also develops, through three stages, the utopia that will redeem this condition. The first stage is romantic nostalgia, a backward glance at Eden from the countryside surrounding Manchester. The second stage occurs in Manchester, as Gaskell mixes romance with a realistic mode, tracing a utopian drive toward death. The third stage is the utopian break with romantic and realistic accounts of the Condition of England and with the inadequate preceding conceptions of utopia. This third stage transforms narrative modes and figures a new mode of production.

How well do voice-hearing assessment measures capture the positive experiences of individuals?

2019 ◽  
Author(s):  
Lucy Armstrong ◽  
Lorna Hogg ◽  
Pamela Charlotte Jacobsen
Keyword(s):  
Systematic Review ◽  
Lived Experience ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Hearing Assessment ◽  
Positive Experiences ◽  
Assessment Measures ◽  
Stage 1 ◽  
The Voice

The first stage of this project aims to identify assessment measures which include items on voice-hearing by way of a systematic review. The second stage is the development of a brief framework of categories of positive experiences of voice hearing, using a triangulated approach, drawing on views from both professionals and people with lived experience. The third stage will involve using the framework to identify any positve aspects of voice-hearing included in the voice hearing assessments identified in stage 1.

scholarly journals When the World Breaks Down: A 3-Stage Existential Model of Nihilism in Schizophrenia

2021 ◽  
pp. 1-24
Author(s):  
Philipp Klar ◽  
Georg Northoff
Keyword(s):  
The Self ◽  
First Person ◽  
Second Stage ◽  
Existential Crisis ◽  
Third Stage ◽  
The World ◽  
Third Person ◽  
Pathological Development ◽  
Sense Of Reality ◽  
Intentional Structure

The existential crisis of nihilism in schizophrenia has been reported since the early days of psychiatry. Taking first-person accounts concerning nihilistic experiences of both the self and the world as vantage point, we aim to develop a dynamic existential model of the pathological development of existential nihilism. Since the phenomenology of such a crisis is intrinsically subjective, we especially take the immediate and pre-reflective first-person perspective’s (FPP) experience (instead of objectified symptoms and diagnoses) of schizophrenia into consideration. The hereby developed existential model consists of 3 conceptualized stages that are nested into each other, which defines what we mean by existential. At the same time, the model intrinsically converges with the phenomenological concept of the self-world structure notable inside our existential framework. Regarding the 3 individual stages, we suggest that the onset or first stage of nihilistic pathogenesis is reflected by phenomenological solipsism, that is, a general disruption of the FPP experience. Paradigmatically, this initial disruption contains the well-known crisis of common sense in schizophrenia. The following second stage of epistemological solipsism negatively affects all possible perspectives of experience, that is, the first-, second-, and third-person perspectives of subjectivity. Therefore, within the second stage, solipsism expands from a disruption of immediate and pre-reflective experience (first stage) to a disruption of reflective experience and principal knowledge (second stage), as mirrored in abnormal epistemological limitations of principal knowledge. Finally, the experience of the annihilation of healthy self-consciousness into the ultimate collapse of the individual’s existence defines the third stage. The schizophrenic individual consequently loses her/his vital experience since the intentional structure of consciousness including any sense of reality breaks down. Such a descriptive-interpretative existential model of nihilism in schizophrenia may ultimately serve as input for future psychopathological investigations of nihilism in general, including, for instance, its manifestation in depression.

The Origins of the Village Revisited: From Nuclear to Extended Households

2002 ◽  
Vol 67 (3) ◽  
pp. 417-433 ◽  
Author(s):  
Kent V. Flannery
Keyword(s):  
Nuclear Family ◽  
Extended Family ◽  
Near East ◽  
Shared Storage ◽  
Nuclear Families ◽  
Second Stage ◽  
Third Stage ◽  
Two Stages ◽  
Extended Households ◽  
The Village

In Mesoamerica and the Near East, the emergence of the village seems to have involved two stages. In the first stage, individuals were distributed through a series of small circular-to-oval structures, accompanied by communal or “shared” storage features. In the second stage, nuclear families occupied substantial rectangular houses with private storage rooms. Over the last 30 years a wealth of data from the Near East, Egypt, the Trans-Caucasus, India, Africa, and the Southwest U.S. have enriched our understanding of this phenomenon. And in Mesoamerica and the Near East, evidence suggests that nuclear family households eventually gave way to a third stage, one featuring extended family households whose greater labor force made possible extensive multifaceted economies.

Reconstruction of Tragus and External Auditory Meatus using Remnant Auricle during Microtia Reconstruction

2018 ◽  
Vol 34 (02) ◽  
pp. 227-229
Author(s):  
Yi-gao Hu ◽  
Wei Ding ◽  
Jun Tan ◽  
Xin Chen ◽  
Tao Luo ◽  
...  
Keyword(s):  
Skin Flap ◽  
Skin Grafting ◽  
External Auditory Meatus ◽  
Reconstruction Technique ◽  
External Ear ◽  
Flap Necrosis ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Thin Skin

AbstractThis article investigates an effective method with which to reconstruct the tragus and external auditory meatus for microtia reconstruction. The external ear was reconstructed using a delayed postauricular skin flap in patients with congenital microtia. After the first stage of delaying the postauricular skin flap and the second stage of otoplasty with ear framework fabricated from autogenous rib cartilage draping with the delayed skin flap, the third stage involved tragus and external auditory meatus canaloplasty. After designing the remnant auricle flap, the lower part was trimmed and the tragus was reconstructed. The upper part was trimmed into a thin skin flap, which was rotated and used to cover the hollowed wound posterosuperior to the tragus so as to mimic the external auditory meatus. If remnant wounds were present, skin grafting was conducted. In total, 121 patients with congenital microtia were treated from March 2010 to March 2016. The reconstructed tragus and external auditory meatus were well formed, and all wounds healed well. No severe complications such as flap necrosis occurred. Six months postoperatively, the morphology of the reconstructed tragus and external auditory meatus was good. Overall, the patients and their families were satisfied. The use of remnant auricle to reconstruct the tragus and external auditory meatus is an effective auricular reconstruction technique.

The kinetics of reaction between permanganate and chlorine ions in acid solutions

2006 ◽  
Vol 80 (5) ◽  
pp. 726-731 ◽  
Author(s):  
A. V. Levanov ◽  
I. V. Kuskov ◽  
E. E. Antipenko ◽  
V. V. Lunin
Keyword(s):  
Acid Solutions ◽  
Chlorine Ions ◽  
Kinetics Of Reaction ◽  
Kinetics Of

Order-disorder phenomena in α -brass - III. Influence of plastic deformation

1960 ◽  
Vol 257 (1290) ◽  
pp. 363-385 ◽  
Keyword(s):  
Plastic Deformation ◽  
Cold Work ◽  
Stored Energy ◽  
High Concentration ◽  
Complex Behaviour ◽  
Second Stage ◽  
Third Stage ◽  
Anneal Hardening ◽  
Two Stages ◽  
Degree Of Order

The evolution of stored energy during heating for specimens of deformed α-brass is quite different from that previously observed for pure metals; the stored energy is much larger and at least three stages of evolution exist. These have been studied for deformation in torsion and tension and the results correlated with measurements of electrical resistivity, density and hardness. The large release of energy in the first two stages is attributed mainly to the return of order destroyed by plastic deformation; the degree of disorder after heavy cold work is much greater than after quenching (part II). However, slight deformation (10% tension) increases the degree of order slightly. The first stage of energy release, below 120 °C, is probably due to rapid reordering assisted by vacancies created during deformation. The second stage represents the bulk of the reordering and some recovery involving rearrangement and annihilation of dislocations. The deformed specimens are probably strain-aged and thus recovery is accompanied by the dispersal of atmospheres of zinc which increases resistivity and decreases density, to some extent counteracting the effects of recovery. The balance of these three processes in stage 2 causes complex behaviour, the magnitude and even the sign of some changes in properties varies with the deformation. Reordering is complete before the beginning of the third stage of further recovery and recrystallization, in which dispersal of atmospheres is again important. Comparison of measurements of energy, resistivity and density suggests that the high concentration of stacking faults contributes to the resistivity. Anneal hardening is observed for the higher deformations and the maximum hardness coincides with the maximum degree of order.

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