scholarly journals Swelling capacity of mixed talc-like/stevensite layers in white/green clay infillings (“deweylite”/ “garnierite”) from serpentine veins of faulted peridotites, New Caledonia

2020 ◽  
Vol 105 (10) ◽  
pp. 1536-1546
Author(s):  
Lionel Fonteneau ◽  
Laurent Caner ◽  
Sabine Petit ◽  
Farid Juillot ◽  
Florian Ploquin ◽  
...  
Keyword(s):  
Ftir Spectroscopy ◽  
New Caledonia ◽  
Layer Charge ◽  
Large Set ◽  
Ambient Temperatures ◽  
Layer Silicates ◽  
Saturated Clay ◽  
Swelling Capacity ◽  
Before And After ◽  
Intimate Mixture

Abstract White (Mg-rich) and green (Ni-rich) clay infillings (“deweylite”/ “garnierite”) found in serpentine veins of faulted peridotite formations from New Caledonia consist of an intimate mixture of fine-grained and poorly ordered 1:1 and 2:1 layer silicates, commonly referred to as non-expandable serpentine-like (SL) and talc-like (TL) minerals. New data on the swelling and shrinking capacity of these layer silicates were gathered from X-ray diffraction (XRD) after saturation of the clay fractions with different cations (Ca2+, Li+, K+), ethylene glycol (EG) solvation, and heat treatments. Simultaneously, layer charge distribution and vacancy density, respectively, were investigated by FTIR spectroscopy on NH4-saturated clay fractions and XRD on Li-saturated clay fractions before and after heating (Hofmann Klemen treatment). Five clay infillings, with dominant 2:1 layer silicates and variable Ni contents, were selected for this study, from a large set of veinlets, according to their swelling capacity. The crystal chemistry of these samples was characterized by FTIR spectroscopy and bulk chemical analyses. The swelling ability of the clay infillings is attributed to the 2:1 layer silicates. It does not seem to be affected by the relative fraction of Mg and Ni in their octahedral sheets. In XRD patterns, the swelling ability is reflected by slight shifts of the basal reflection of the 2:1 layer silicates toward low angles for bulk samples and by splitting of the peak into two contributions for clay fractions saturated with Ca (or Li) and solvated with EG. The split increases with the swelling capacity of the sample. It originates mainly from octahedral-layer charge generated by vacant sites. Such results lead us to consider the 2:1 layer silicates of the infillings as an intimate mixture of non-expandable (TL) and expandable (stevensite) phases. In agreement with previous studies that suggested a contribution of hydrothermal processes in the alteration of serpentine species into 2:1 layer silicates, we propose that the proportion of expandable phases in the clay infillings (or vacancy sites in the octahedral sheets of the 2:1 layer silicates) could be used as an efficient means for assessing the temperature of their formation. Clay infillings mostly made of stevensite would have formed at ambient temperatures, whereas those consisting mainly of non-expandable TL would have formed at higher temperatures.

Prediction Reliability of Container Terminal Simulation Models

2010 ◽  
pp. 315-335
Author(s):  
Armando Cartenì
Keyword(s):  
Decision Support ◽  
Decision Support System ◽  
Support System ◽  
Optimization Problem ◽  
Container Terminal ◽  
Simulation Models ◽  
Large Set ◽  
Model Application ◽  
Before And After ◽  
Prediction Reliability

In this chapter attention is focused on the container terminal optimization problem, given that today most international cargo is transported through seaports and on containerized vessels. In this context, in order to manage a container terminal it is sometimes necessary to develop a Decision Support System (DSS). This chapter investigated the prediction reliability of container terminal simulation models (DSS), through a before and after analysis, taking advantage of some significant investment made by the Salerno Container Terminal (Italy) between 2003 and 2008. In particular, disaggregate and an aggregate simulation models implemented in 2003 were validated with a large set of data acquired in 2008 after some structural and functional terminal modifications. Through this analysis it was possible to study both the mathematical details required for model application and the field of application (prediction reliability) of the different simulation approaches implemented.

scholarly journals Fall Mole Cricket Control on Golf Courses in South Mississippi, 1992

1994 ◽  
Vol 19 (1) ◽  
pp. 309-309
Author(s):  
Joseph P. Harris
Keyword(s):  
Gulf Coast ◽  
Golf Course ◽  
Golf Courses ◽  
Clay Loam ◽  
Jackson County ◽  
Ambient Temperatures ◽  
Time Of Application ◽  
Mole Cricket ◽  
Before And After ◽  
Pre Treatment

Abstract This experiment was conducted on fairways at the Jackson County Golf Course in Jackson County on the Gulf Coast of Mississippi. Soil type was sandy clay loam. Experimental design was a RCB with 4 replications. Each replication was 10,000 ft2. Treatments were made on 7 Oct between 4:00 and 5:30 p.m. Both treatments were applied with a Snyder Polyolefin Agro-Tank tractor mounted hydraulic sprayer. Total spray volume was 50 gal water/acre using 8003 T-jet flat nozzles with 50 psi. Immediately before and after treatment, VS inch irrigation water was applied to all plots except the Orthene treated plots. All plots were irrigated with V* inch of water each afternoon after treatment for four weeks. Rainfall of 1.5, 0.5, and 1.5 inches occurred on 1,3, and 4 Nov, respectively. At the time of application soil and ambient temperatures were 73° and 75° F, respectively. Relative humidity was moderate with a cloud cover of 20%. Mole cricket damage ratings were made using a 1 m2 frame divided into nine equal, square-shaped sections. The frame was placed on the ground in 20 locations/rep. The presence of mounds and tunnels was determined visually and by touch. Damage ranged from zero (no damage in any of the nine sections) to nine (nine sections contained mounds and/or tunnels). Pre-treatment counts were made on 6 Oct and post-treatment counts were made on 21 Oct and 4 Nov.

scholarly journals Synthesis of Lipase-Immobilized CeO2 Nanorods as Heterogeneous Nano-Biocatalyst for Optimized Biodiesel Production from Eruca sativa Seed Oil

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 231 ◽  
Author(s):  
Anam Fatima ◽  
Muhammad Waseem Mumtaz ◽  
Hamid Mukhtar ◽  
Sadia Akram ◽  
Tooba Touqeer ◽  
...  
Keyword(s):  
Ftir Spectroscopy ◽  
Alternative Energy ◽  
Immobilized Lipase ◽  
Hydrothermal Process ◽  
Biodiesel Production ◽  
Attractive Alternative ◽  
Eruca Sativa ◽  
Alternative Energy Sources ◽  
Biodiesel Synthesis ◽  
Before And After

Biodiesel has emerged as one of the most attractive alternative energy sources to meet the growing needs of energy. Many approaches have been adopted for biodiesel synthesis. In the present work, biodiesel was produced from non-edible Eruca sativa oil using nano-biocatalyst-catalysed transesterification. Nano-biocatalyst (CeO2@PDA@A. terreus Lipase) was developed via the immobilization of lipase on polydopamine coated ceria nanorods, and CeO2 nanorods were developed via a hydrothermal process. The mean diameter of nanorods were measured to be 50–60 nm, while their mean length was 150–200 nm. Lipase activity before and after immobilization was measured to be 18.32 and 16.90 U/mg/min, respectively. The immobilized lipase depicted high stability at high temperature and pH. CeO2@PDA@A. terreus Lipase-catalysed transesterification resulted in 89.3% yield of the product. Process optimization through response surface methodology was also executed, and it was depicted that the optimum/maximum E. sativa oil-based biodiesel yield was procured at conditions of 10% CeO2@PDA@A. terreus Lipase, 6:1 methanol/oil ratio, 0.6% water content, 35 °C reaction temperature, and 30 h reaction time. The fuel compatibility of synthesized biodiesel was confirmed via the estimation of fuel properties that were in agreement with the ASTM D standard. The nanorods and dopamine-modified nanorods were characterized by FTIR spectroscopy, SEM, and energy dispersive X-ray (EDX), while conversion of E. sativa oil to biodiesel was confirmed by GC/MS and FTIR spectroscopy. Conclusively, it was revealed that CeO2@PDA@A. terreus Lipase has potential to be employed as an emphatic nano-biocatalyst.

scholarly journals Assessment of Absorption of Glycated Nail Proteins in Patients with Diabetes Mellitus and Diabetic Retinopathy

Medicina ◽  
2020 ◽  
Vol 56 (12) ◽  
pp. 658
Author(s):  
Ieva Jurgeleviciene ◽  
Daiva Stanislovaitiene ◽  
Vacis Tatarunas ◽  
Marius Jurgelevicius ◽  
Dalia Zaliuniene
Keyword(s):  
Diabetes Mellitus ◽  
Diabetic Retinopathy ◽  
Ftir Spectroscopy ◽  
Region Of Interest ◽  
Control Group ◽  
Before And After ◽  
Patients With Diabetes ◽  
Long Term Observation

Background and objectives: Glycation occurs in a variety of human tissues and organs. Knowledge about the relationship between predictive biochemical factors such as absorption of glycated nail proteins and severity of type 2 diabetes mellitus (DM) and diabetic retinopathy (DR) remains limited. Materials and Methods: The study group consisted of patients with type 2 DM and DR (n = 32) and a control group (n = 28). Each patient underwent a comprehensive ophthalmic examination. The glycation process in nail clippings was evaluated in stages of in vitro glycation and deglycation stages. ATR–FTIR spectroscopy was used to calculate the infrared absorption in the region of interest. The absorption of solutions with nail clippings was evaluated by NanoDrop spectrophotometry. Absorption spectra differences before and after the exposure to fructosamine 3-kinase were compared between DM patients with DR and the control group. Results: The absorption of glycated nail protein greater than 83.00% increased the chance of developing DM and DR (OR = 15.909, 95% CI 3.914–64.660, p < 0.001). Absorption of glycated nail protein by ATR–FTIR spectroscopy in patients with DM and DR in vitro glycation was statistically significantly higher than in the control group; also absorption of solution with nails by NanoDrop spectroscopy was statistically significantly higher than in controls in vitro glycation and in vitro deglycation. After exposure to fructosamine 3-kinase, absorption of nail protein in DM + severe/proliferative DR group was statistically significantly lower in comparison with DM + mild/moderate group DR. Conclusions: Evaluation of glycated nail protein could be applied to evaluate the risk of having DM and for long-term observation of DM control.

scholarly journals Contagion of the Subprime Financial Crisis on Frontier Stock Markets: A Copula Analysis

Economies ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 15 ◽  
Author(s):  
Wahbeeah Mohti ◽  
Andreia Dionísio ◽  
Paulo Ferreira ◽  
Isabel Vieira
Keyword(s):  
Financial Crisis ◽  
Stock Markets ◽  
Large Set ◽  
Subprime Crisis ◽  
Relative Level ◽  
Copula Models ◽  
Before And After ◽  
The Usa ◽  
International Investors ◽  
Geographical Diversification

This study assesses contagion from the USA subprime financial crisis on a large set of frontier stock markets. Copula models were used to investigate the structure of dependence between frontier markets and the USA, before and after the occurrence of the crisis. Statistically significant evidence of contagion could only be found in the European region, with the markets of Croatia and Romania being affected. The remaining European markets in our sample and the others, located in America, Middle East, Africa, and Asia, appear to have been isolated from the subprime crisis impact. These results are useful for international investors interested in enlarging the geographical diversification of their portfolios, but also for the considered countries’ policymakers who should attempt to improve the attractiveness of stock markets for domestic and foreign investors while simultaneously attempting to maintain their relative level of insulation against future foreign crises.

Cold-defense function of brown adipose tissue during sleep

1993 ◽  
Vol 265 (5) ◽  
pp. R1060-R1064 ◽  
Author(s):  
M. Calasso ◽  
E. Zantedeschi ◽  
P. L. Parmeggiani
Keyword(s):  
Adipose Tissue ◽  
Ambient Temperature ◽  
Brown Adipose Tissue ◽  
Nasal Mucosa ◽  
Interscapular Brown Adipose Tissue ◽  
Ambient Temperatures ◽  
Brown Adipose ◽  
Before And After ◽  
Defense Function

Rats with chronically implanted electroencephalograph scalp electrodes and thermistors were exposed to 24 and 4 degrees C ambient temperatures during the light hours before and after acclimation to 4 degrees C ambient temperature for 9 days. During synchronized sleep, deep interscapular temperature was higher at 4 degrees C than at 24 degrees C both before and after acclimation to cold. After ablation of brown adipose tissue, deep interscapular temperature was lower at 4 degrees C than at 24 degrees C during synchronized sleep. In the presence of brown adipose tissue, deep interscapular temperature decreased sharply during desynchronized sleep at 4 degrees C both before and after acclimation to cold. This decrease was subsequent to and correlated with an increase in the temperature of the nasal mucosa. The decrease in deep interscapular temperature during desynchronized sleep at 4 degrees C ambient temperature was markedly reduced by ablation of the interscapular brown adipose tissue.

High-flux neutron irradiation of boron trioxide analyzed with Raman and FTIR spectroscopy

2020 ◽  
Vol 34 (18) ◽  
pp. 2050160
Author(s):  
Matlab N. Mirzayev
Keyword(s):  
Raman Spectrum ◽  
Ftir Spectroscopy ◽  
Functional Groups ◽  
Neutron Irradiation ◽  
Spectrum Analysis ◽  
Boron Oxide ◽  
Fast Neutrons ◽  
Raman Analysis ◽  
Before And After ◽  
Flux Formula

Boron oxide nanopowder is widely used in the production of special glasses and nuclear technology. This paper reports on the optical properties and investigates the formation of new bonds on the structure of nanoboron oxide. In this work, high purity boron oxide samples were irradiated using a energy upto 1 MeV fast neutrons with fluences in the range of [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and the neutron flux [Formula: see text] at the room-temperature. Optical properts were determined using Raman spectrum analysis and spectroscopy Fourier transform infrared (FTIR) spectroscopy. FTIR and Raman spectrum analysis were used to explain the chemical bonds and functional groups of nanoboron oxide samples before and after neutron irradiation. When the irradation fluence on [Formula: see text] was increased upto [Formula: see text] it resulted in the formation of a new functional groups [Formula: see text]. From the Raman analysis, the [Formula: see text] was observed to start amorphization after neutron irradiation.

Characterization, Modification and Rheology of Green Clay

2015 ◽  
Vol 820 ◽  
pp. 60-64
Author(s):  
Leila Verônica da Rocha-Gomes ◽  
Antônio José Santana ◽  
Camila Martini Matos ◽  
Valquíria de Fátima Justo ◽  
Maria Das Graças Silva-Valenzuela ◽  
...  
Keyword(s):  
Water Absorption ◽  
Rheological Properties ◽  
Apparent Density ◽  
Industrial Applications ◽  
Clay Sample ◽  
Oil Drilling ◽  
Smectite Clays ◽  
Swelling Capacity ◽  
Before And After ◽  
Green Clay

Smectite clays or bentonites are used in several industrial applications. The aim of this study was to describe the characterization and organophilization of a green clay sample coming from the State of Paraíba, Brazil. The clay was characterized by XRD, XRF, CEC, SEM, stereoscopic microscopy, Fann viscosity (before and after the organophilization process), swelling capacity in water and some organic solvents. Prismatic specimens were conformed by pressing, for which were conformed the mechanical sthegth after drying at 110°C and after burning at 950°C. The burned specimens were analyzed to evaluate dimensional variations, water absorption, apparent porosity and apparent density. XRD showed that the sample was constituted mainly for montmorillonite claymineral. Analysis of rheological properties of the modified clay indicates its potential to meet the specifications of the standard N-2604 of Petrobras, concerning clays used to oil drilling.

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