Search results for: calcium permeability
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1237

Search results for: calcium permeability

1237 Experimental Investigation on Correlation Between Permeability Variation and Sabkha Soil Salts Dissolution

Authors: Fahad A. Alotaibi

Abstract:

An increase in salt dissolution rate with continuous water flow is expected to lead to the progressive collapse of the soil structure. Evaluation of the relationship between soil salt dissolution and the variation of sabkha soil permeability in terms of type, rate, and quantity in order to assure construction safety in these environments. The current study investigates the relationship of soil permeability with the rate of dissolution of calcium (Ca2+), sulfate (SO4-2), chloride (CL−1), magnesium (Mg2+), sodium (Na+), and potassium (K+1) ions. Results revealed an increase in sabkha soil permeability with the rate of ions dissolution. This makes the efficiency of using a waterproofing stabilization agent in the reduction of sabkha salts dissolution the main criterion is selecting suitable stabilizing method.

Keywords: sabkha, permeability, salts, dissolution

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1236 [Keynote Talk]: A Comparative Study on Air Permeability Properties of Multilayered Nonwoven Structures

Authors: M. Kucukali Ozturk, B. Nergis, C. Candan

Abstract:

Air permeability plays an important role for applications such as filtration, thermal and acoustic insulation. The study discussed in this paper was conducted in an attempt to investigate air permeability property of various combinations of nonwovens. The PROWHITE air permeability tester was used for the measurement of the air permeability of the samples in accordance with the relevant standards and a comparative study of the results were made. It was found that the fabric mass per unit area was closely related to the air-permeability. The air permeability decreased with the increase in mass per unit area. Additionally, the air permeability of nonwoven fabrics decreased with the increase in thickness. Moreover, air permeability of multilayered SMS nonwoven structures was lower than those of single layered ones.

Keywords: air permeability, mass per unit area, nonwoven structure, polypropylene nonwoven, thickness

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1235 Comparison of the Hydration Products of Commercial and Experimental Calcium Silicate Cement: The Preliminary Observational Study

Authors: Seok Woo Chang

Abstract:

Aim: The objective of this study was to compare and evaluate the hydration products of commercial and experimental calcium silicate cement. Materials and Methods: The commercial calcium silicate cement (ProRoot MTA, Dentsply) and experimental calcium silicate cement (n=10) were mixed with distilled water (water/powder ratio = 20 w/w) and stirred at room temperature for 10 hours. These mixtures were dispersed on wafer and dried for 12 hours at room temperature. Thereafter, the dried specimens were examined with Scanning Electron Microscope (SEM). Electron Dispersive Spectrometry (EDS) was also carried out. Results: The commercial calcium silicate cement (ProRoot MTA) and experimental calcium silicate cement both showed precipitation of rod-like and globule-like crystals. Based on EDS analysis, these precipitates were supposed to be calcium hydroxide or calcium silicate hydrates. The degree of formation of these precipitates was higher in commercial MTA. Conclusions: Based on the results, both commercial and experimental calcium silicate cement had ability to produce calcium hydroxide or calcium silicate hydrate precipitates.

Keywords: calcium silicate cement, ProRoot MTA, precipitation, calcium hydroxide, calcium silicate hydrate

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1234 Prediction of in situ Permeability for Limestone Rock Using Rock Quality Designation Index

Authors: Ahmed T. Farid, Muhammed Rizwan

Abstract:

Geotechnical study for evaluating soil or rock permeability is a highly important parameter. Permeability values for rock formations are more difficult for determination than soil formation as it is an effect of the rock quality and its fracture values. In this research, the prediction of in situ permeability of limestone rock formations was predicted. The limestone rock permeability was evaluated using Lugeon tests (in-situ packer permeability). Different sites which spread all over the Riyadh region of Saudi Arabia were chosen to conduct our study of predicting the in-situ permeability of limestone rock. Correlations were deducted between the values of in-situ permeability of the limestone rock with the value of the rock quality designation (RQD) calculated during the execution of the boreholes of the study areas. The study was performed for different ranges of RQD values measured during drilling of the sites boreholes. The developed correlations are recommended for the onsite determination of the in-situ permeability of limestone rock only. For the other sedimentary formations of rock, more studies are needed for predicting the actual correlations related to each type.

Keywords: In situ, packer, permeability, rock, quality

Procedia PDF Downloads 343
1233 Can Bone Resorption Reduce with Nanocalcium Particles in Astronauts?

Authors: Ravi Teja Mandapaka, Prasanna Kumar Kukkamalla

Abstract:

Poor absorption of calcium, elevated levels in serum and loss of bone are major problems of astronauts during space travel. Supplementation of calcium could not reveal this problem. In normal condition only 33% of calcium is absorbed from dietary sources. In this paper effect of space environment on calcium metabolism was discussed. Many surprising study findings were found during literature survey. Clinical trials on ovariectomized mice showed that reduction of calcium particles to nano level make them more absorbable and bioavailable. Control of bone loss in astronauts in critical important In Fortification of milk with nana calcium particles showed reduces urinary pyridinoline, deoxypyridinoline levels. Dietary calcium and supplementation do not show much retention of calcium in zero gravity environment where absorption is limited. So, the fortification of foods with nano calcium particles seemed beneficial for astronauts during and after space travel in their speedy recovery.

Keywords: nano calcium, astronauts, fortification, supplementation

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1232 The Fundamental Research and Industrial Application on CO₂+O₂ in-situ Leaching Process in China

Authors: Lixin Zhao, Genmao Zhou

Abstract:

Traditional acid in-situ leaching (ISL) is not suitable for the sandstone uranium deposit with low permeability and high content of carbonate minerals, because of the blocking of calcium sulfate precipitates. Another factor influences the uranium acid in-situ leaching is that the pyrite in ore rocks will react with oxidation reagent and produce lots of sulfate ions which may speed up the precipitation process of calcium sulphate and consume lots of oxidation reagent. Due to the advantages such as less chemical reagent consumption and groundwater pollution, CO₂+O₂ in-situ leaching method has become one of the important research areas in uranium mining. China is the second country where CO₂+O₂ ISL has been adopted in industrial uranium production of the world. It is shown that the CO₂+O₂ ISL in China has been successfully developed. The reaction principle, technical process, well field design and drilling engineering, uranium-bearing solution processing, etc. have been fully studied. At current stage, several uranium mines use CO₂+O₂ ISL method to extract uranium from the ore-bearing aquifers. The industrial application and development potential of CO₂+O₂ ISL method in China are summarized. By using CO₂+O₂ neutral leaching technology, the problem of calcium carbonate and calcium sulfate precipitation have been solved during uranium mining. By reasonably regulating the amount of CO₂ and O₂, related ions and hydro-chemical conditions can be controlled within the limited extent for avoiding the occurrence of calcium sulfate and calcium carbonate precipitation. Based on this premise, the demand of CO₂+O₂ uranium leaching has been met to the maximum extent, which not only realizes the effective leaching of uranium, but also avoids the occurrence and precipitation of calcium carbonate and calcium sulfate, realizing the industrial development of the sandstone type uranium deposit.

Keywords: CO₂+O₂ ISL, industrial production, well field layout, uranium processing

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1231 Numerical Model to Study Calcium and Inositol 1,4,5-Trisphosphate Dynamics in a Myocyte Cell

Authors: Nisha Singh, Neeru Adlakha

Abstract:

Calcium signalling is one of the most important intracellular signalling mechanisms. A lot of approaches and investigators have been made in the study of calcium signalling in various cells to understand its mechanisms over recent decades. However, most of existing investigators have mainly focussed on the study of calcium signalling in various cells without paying attention to the dependence of calcium signalling on other chemical ions like inositol-1; 4; 5 triphosphate ions, etc. Some models for the independent study of calcium signalling and inositol-1; 4; 5 triphosphate signalling in various cells are present but very little attention has been paid by the researchers to study the interdependence of these two signalling processes in a cell. In this paper, we propose a coupled mathematical model to understand the interdependence of inositol-1; 4; 5 triphosphate dynamics and calcium dynamics in a myocyte cell. Such studies will provide the deeper understanding of various factors involved in calcium signalling in myocytes, which may be of great use to biomedical scientists for various medical applications.

Keywords: calcium signalling, coupling, finite difference method, inositol 1, 4, 5-triphosphate

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1230 Laboratory Measurement of Relative Permeability of Immiscible Fluids in Sand

Authors: Khwaja Naweed Seddiqi, Shigeo Honma

Abstract:

Relative permeability is the important parameter controlling the immiscible displacement of multiphase fluids flow in porous medium. The relative permeability for immiscible displacement of two-phase fluids flow (oil and water) in porous medium has been measured in this paper. As a result of the experiment, irreducible water saturation, Swi, residual oil saturation, Sor, and relative permeability curves for Kerosene, Heavy oil and Lubricant oil were determined successfully.

Keywords: relative permeability, two-phase flow, immiscible displacement, porous medium

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1229 Combinatory Nutrition Supplementation: A Case of Synergy for Increasing Calcium Bioavailability

Authors: Daniel C. S. Lim, Eric Y. M. Yeo, W. Y. Tan

Abstract:

This paper presents an overview of how calcium interacts with the various essential nutrients within an environment of cellular and hormonal interactions for the purpose of increasing bioavailability to the human body. One example of such interactions can be illustrated with calcium homeostasis. This paper gives an in-depth discussion on the possible interactive permutations with various nutrients and factors leading to the promotion of calcium bioavailability to the body. The review hopes to provide further insights into how calcium supplement formulations can be improved to better influence its bioavailability in the human body.

Keywords: bioavailability, environment of cellular and hormonal interactions, nutritional combinations, synergistic

Procedia PDF Downloads 363
1228 Evaluating the Permeability Coefficient of Sandy Soil for Grouting to Reinforce Soft Soil in Binh Duong, Vietnam

Authors: Trung Le Thanh

Abstract:

Soil permeability coefficient is an important parameter that affects the effectiveness of mortar restoration work to reinforce soft soil. Currently, there are many methods to determine the permeability coefficient of ground through laboratory and field experiments. However, the value of the permeability coefficient is determined very differently depending on the geology in general and the sand base in particular. This article presents how to determine the permeability coefficient of sand foundation in Phu My Ward, Tan Uyen City, Binh Duong. The author analyzes and evaluates the advantages and disadvantages of assessment methods based on the data and results obtained, and on that basis recommends a suitable method for determining the permeability coefficient for sand foundations. The research results serve the evaluation of the effectiveness of grouting to reinforce soft ground in general, and grouting of bored piles in particular.

Keywords: permeability coefficient, soft soil, shaft grouting, post grouting, jet grouting

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1227 Sulfate Attack on Pastes Made with Different C3A and C4AF Contents and Stored at 5°C

Authors: Konstantinos Sotiriadis, Radosław Mróz

Abstract:

In the present work the internal sulfate attack on pastes made from pure clinker phases was studied. Two binders were produced: (a) a binder with 2% C3A and 18% C4AF content; (b) a binder with 10% C3A and C4AF content each. Gypsum was used as the sulfate bearing compound, while calcium carbonate added to differentiate the binders produced. The phases formed were identified by XRD analysis. The results showed that ettringite was the deterioration phase detected in the case of the low C3A content binder. Carbonation occurred in the specimen without calcium carbonate addition, while portlandite was observed in the one containing calcium carbonate. In the case of the high C3A content binder, traces of thaumasite were detected when calcium carbonate was not incorporated in the binder. A solid solution of thaumasite and ettringite was found when calcium carbonate was added. The amount of C3A had not fully reacted with sulfates, since its corresponding peaks were detected.

Keywords: tricalcium aluminate, calcium aluminate ferrite, sulfate attack, calcium carbonate, low temperature

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1226 The Effect of Nanofiber Web on Thermal Conductivity, Air and Water Vapor Permeability

Authors: Ilkay Ozsev Yuksek, Nuray Ucar, Zeynep Esma Soygur, Yasemin Kucuk

Abstract:

In this study, composite fabrics with polyacrylonitrile electrospun nanofiber deposited onto quilted polyester fabric have been produced in order to control the isolation properties such as water vapor permeability, air permeability and thermal conductivity. Different nanofiber webs were manufactured by changing polymer concentration from 10% to 16% and by changing the deposition time from 1 to 3 hours. Presence of nanofiber layer on the quilted fabric results to an increase of an isolation, i.e., a decrease of the moisture vapor transport rates at 20%, decrease of thermal conductivity at 15% and a decrease of air permeability values at 50%.

Keywords: nanofiber/fabric composites, electrospinning, isolation, thermal conductivity, moisture vapor transport, air permeability

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1225 Studies on the Recovery of Calcium and Magnesium from Red Seawater by Nanofiltration Membrane

Authors: Mohamed H. Sorour, Hayam F. Shaalan, Heba A. Hani, Mahmoud A. El-Toukhy

Abstract:

This paper reports the results of nanofiltration (NF) polymeric membrane for the recovery of divalent ions (calcium and magnesium) from Red Seawater. Pilot plant experiments have been carried out using Alfa-Laval (NF 2517/48) membrane module. System was operated in both total recirculation mode (permeate and brine) and brine recirculation mode under hydraulic pressure of 15 bar. Impacts of some chelating agents on both flux and rejection have been also investigated. Results indicated that pure water permeability ranges from 17 to 85.5 L/m²h at 2-15 bar. Comparison with seawater permeability under the same operating pressure values reveals lower values of 8.9-31 L/m²h manifesting the effect of the osmotic pressure of seawater. Overall total dissolved solids (TDS) reduction was almost constant without incorporation of chelating agents. On the contrary of expectations, the use of chelating agents N-(2-hydroxyethyl) ethylene diamine-N,N´,N´-triacetic acid (HEDTA) and ethylene glycol bis (2-aminoethyl ether)-N,N,N´,N´-tetraacetic acid (EGTA) showed flux decline of about 3-15%. Analysis of rejection data of total recirculation mode showed reasonable rejection values of 35%, 59% and 90% for Ca, Mg and SO₄, respectively. Operating under brine recirculation mode only showed a decrease of rejection to 33%, 56% and 86% for Ca, Mg and SO₄, respectively. The use of chelating agents has no substantial effect on NF membrane performance except for increasing the total Ca rejection to 48 and 65% for EGTA and HEDTA, respectively. Results, in general, confirmed the powerful separation of NF technology for softening and recovery of divalent ions from seawater. It is anticipated that increasing operating pressure beyond the limits of our investigations would improve the rejection and flux values. A trade-off should be considered between operating cost (due to higher pressure and marginal benefits as manifested by expected improved performance). The experimental results fit well with the formulated rejection empirical correlations and the published ones.

Keywords: nanofiltration, seawater, recovery, calcium, magnesium

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1224 The Effects of Different Types of Cement on the Permeability of Deep Mixing Columns

Authors: Mojebullah Wahidy, Murat Olgun

Abstract:

In this study, four different types of cement are used to investigate the permeability of DMC (Deep Mixing Column) in the clay. The clay used in this research is in the kaolin group, and the types of cement are; CEM I 42.5.R. normal portland cement, CEM II/A-M (P-L) pozzolan doped cement, CEM III/A 42.5 N blast furnace slag cement and DMFC-800 fine-grained portland cement. Firstly, some rheological tests are done on every cement, and a 0.9 water/cement ratio is selected as the appropriate ratio. This ratio is used to prepare the small-scale DMCs for all types of cement with %6, %9, %12, and %15, which are determined as the dry weight of the clay. For all the types of cement, three samples were prepared in every percentage and were kept on curing for 7, 14, and 28 days for permeability tests. As a result of the small-scale DMCs, permeability tests, a %12 selected for big-scale DMCs. A total of five big scales DMC were prepared by using a %12-cement and were kept for 28 days curing for permeability tests. The results of the permeability tests show that by increasing the cement percentage and curing time of all DMCs, the permeability coefficient (k) is decreased. Despite variable results in different cement ratios and curing time in general, samples treated by DMFC-800 fine-grained cement have the lowest permeability coefficient. Samples treated with CEM II and CEM I cement types were the second and third lowest permeable samples. The highest permeability coefficient belongs to the samples that were treated with CEM III cement type.

Keywords: deep mixing column, rheological test, DMFC-800, permeability test

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1223 Soil Improvement through Utilization of Calcifying Bhargavaea cecembensis N1 in an Affordable Whey Culture Medium

Authors: Fatemeh Elmi, Zahra Etemadifar

Abstract:

Improvement of soil mechanical properties is crucial before its use in construction, as the low mechanical strength and unstable structure of soil in many parts of the world can lead to the destruction of engineering infrastructure, resulting in financial and human losses. Although, conventional methods, such as chemical injection, are often utilized to enhance soil strength and stiffness, they are generally expensive, require heavy machinery, and cause significant environmental effects due to chemical usage, and also disrupt urban infrastructure. Moreover, they are not suitable for treating large volume of soil. Recently, an alternative method to improve various soil properties, including strength, hardness, and permeability, has received much attention: the application of biological methods. One of the most widely used is biocementation, which is based on the microbial precipitation of calcium carbonte crystalls using ureolytic bacteria However, there are still limitations to its large-scale use that need to be resolved before it can be commercialized. These issues have not received enough attention in prior research. One limitation of MICP (microbially induced calcium carbonate precipitation) is that microorganisms cannot operate effectively in harsh and variable environments, unlike the controlled conditions of a laboratory. Another limitation of applying this technique on a large scale is the high cost of producing a substantial amount of bacterial culture and reagents required for soil treatment. Therefore, the purpose of the present study was to investigate soil improvement using the biocementation activity of poly-extremophile, calcium carbonate crystal- producing bacterial strain, Bhargavaea cecembensis N1, in whey as an inexpensive medium. This strain was isolated and molecularly identified from sandy soils in our previous research, and its 16S rRNA gene sequences was deposited in the NCBI Gene Bank with an accession number MK420385. This strain exhibited a high level of urease activity (8.16 U/ml) and produced a large amount of calcium carbonate (4.1 mg/ ml). It was able to improve the soil by increasing the compressive strength up to 205 kPa and reducing permeability by 36%, with 20% of the improvement attributable of calcium carbonate production. This was achieved using this strain in a whey culture medium. This strain can be an eco-friendly and economical alternative to conventional methods in soil stabilization, and other MICP related applications.

Keywords: biocementation, Bhargavaea cecembensis, soil improvement, whey culture medium

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1222 A Neural Network Modelling Approach for Predicting Permeability from Well Logs Data

Authors: Chico Horacio Jose Sambo

Abstract:

Recently neural network has gained popularity when come to solve complex nonlinear problems. Permeability is one of fundamental reservoir characteristics system that are anisotropic distributed and non-linear manner. For this reason, permeability prediction from well log data is well suited by using neural networks and other computer-based techniques. The main goal of this paper is to predict reservoir permeability from well logs data by using neural network approach. A multi-layered perceptron trained by back propagation algorithm was used to build the predictive model. The performance of the model on net results was measured by correlation coefficient. The correlation coefficient from testing, training, validation and all data sets was evaluated. The results show that neural network was capable of reproducing permeability with accuracy in all cases, so that the calculated correlation coefficients for training, testing and validation permeability were 0.96273, 0.89991 and 0.87858, respectively. The generalization of the results to other field can be made after examining new data, and a regional study might be possible to study reservoir properties with cheap and very fast constructed models.

Keywords: neural network, permeability, multilayer perceptron, well log

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1221 Stochastic Modeling of Secretion Dynamics in Inner Hair Cells of the Auditory Pathway

Authors: Jessica A. Soto-Bear, Virginia González-Vélez, Norma Castañeda-Villa, Amparo Gil

Abstract:

Glutamate release of the cochlear inner hair cell (IHC) ribbon synapse is a fundamental step in transferring sound information in the auditory pathway. Otoferlin is the calcium sensor in the IHC and its activity has been related to many auditory disorders. In order to simulate secretion dynamics occurring in the IHC in a few milliseconds timescale and with high spatial resolution, we proposed an active-zone model solved with Monte Carlo algorithms. We included models for calcium buffered diffusion, calcium-binding schemes for vesicle fusion, and L-type voltage-gated calcium channels. Our results indicate that calcium influx and calcium binding is managing IHC secretion as a function of voltage depolarization, which in turn mean that IHC response depends on sound intensity.

Keywords: inner hair cells, Monte Carlo algorithm, Otoferlin, secretion

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1220 Two Dimensional Finite Element Model to Study Calcium Dynamics in Fibroblast Cell with Excess Buffer Approximation Involving ER Flux and SERCA Pump

Authors: Mansha Kotwani

Abstract:

The specific spatio-temporal calcium concentration patterns are required by the fibroblasts to maintain its structure and functions. Thus, calcium concentration is regulated in cell at different levels in various activities of the cell. The variations in cytosolic calcium concentration largely depend on the buffers present in cytosol and influx of calcium into cytosol from ER through IP3Rs or Raynodine receptors followed by reuptake of calcium into ER through sarcoplasmic/endoplasmic reticulum ATPs (SERCA) pump. In order to understand the mechanisms of wound repair, tissue remodeling and growth performed by fibroblasts, it is of crucial importance to understand the mechanisms of calcium concentration regulation in fibroblasts. In this paper, a model has been developed to study calcium distribution in NRK fibroblast in the presence of buffers and ER flux with SERCA pump. The model has been developed for two dimensional unsteady state case. Appropriate initial and boundary conditions have been framed along with physiology of the cell. Finite element technique has been employed to obtain the solution. The numerical results have been used to study the effect of buffers, ER flux and source amplitude on calcium distribution in fibroblast cell.

Keywords: buffers, IP3R, ER flux, SERCA pump, source amplitude

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1219 Modification of Toothpaste Formula Using Pineapple Cobs and Eggshell Waste as a Way to Decrease Dental Caries

Authors: Achmad Buhori, Reza Imam Pratama, Tissa Wiraatmaja, Wanti Megawati

Abstract:

Data from many countries indicates that there is a marked increase of dental caries. The increases in caries appear to occur in lower socioeconomic groups. It is possible that the benefits of prevention of dental caries are not reaching these groups. However, there is a way to decrease dental caries by adding 5% of bromelain and calcium as an active agent in toothpaste. Bromelain can break glutamine-alanine bond and arginine-alanine bond which is a constituent of amino acid that causes dental plague which is one of the factors of dental caries. Calcium help rebuilds the teeth by strengthening and repairing enamel. Bromelain can be found from the extraction of pineapple (Ananas comosus) cobs (88.86-94.22 % of bromelain recovery during extraction based on the enzyme unit) and calcium can be taken from eggshell (95% of dry eggshell consist of calcium). The aim of this experiment is to make a toothpaste which contains bromelain and calcium as an effective, cheap, and healthy way to decrease dental caries around the world.

Keywords: bromelain, calcium, dental caries, dental plague, toothpaste

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1218 Modified Evaluation of the Hydro-Mechanical Dependency of the Water Coefficient of Permeability of a Clayey Sand with a Novel Permeameter for Unsaturated Soils

Authors: G. Adelian, A. Mirzaii, S. S. Yasrobi

Abstract:

This paper represents data of an extensive experimental laboratory testing program for the measurement of the water coefficient of permeability of clayey sand in different hydraulic and mechanical boundary conditions. A novel permeameter was designed and constructed for the experimental testing program, suitable for the study of flow in unsaturated soils in different hydraulic and mechanical loading conditions. In this work, the effect of hydraulic hysteresis, net isotropic confining stress, water flow condition, and sample dimensions are evaluated on the water coefficient of permeability of understudying soil. The experimental results showed a hysteretic variation for the water coefficient of permeability versus matrix suction and degree of saturation, with higher values in drying portions of the SWCC. The measurement of the water permeability in different applied net isotropic stress also signified that the water coefficient of permeability increased within the increment of net isotropic consolidation stress. The water coefficient of permeability also appeared to be independent of different applied flow heads, water flow condition, and sample dimensions.

Keywords: water permeability, unsaturated soils, hydraulic hysteresis, void ratio, matrix suction, degree of saturation

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1217 An Experimental Study of the Influence of Flow Rate on Formation Damage at Different pH

Authors: Khabat M. Ahmad

Abstract:

This experiment focuses on the reduction of permeability (formation damage) as a result of fines migration by changing pH and flow rate on core plugs selected from sandstone reservoir of Pannonian basin (Upper Miocene, East Hungary). The main objective of coreflooding experiments was to investigate the influence of both high and low pH fluids and the flow rate on stability of clay minerals. The selected core samples were examined by X-ray powder diffraction (XRD) for bulk mineralogical and clay mineral composition. The shape, position, distribution and type of clay minerals within the core samples were diagnosed by scanning electron microscopy and energy dispersive spectroscopy (SEM- EDS). The basic petrophysical properties such as porosity and initial permeability were determined prior to experiments. The special core analysis (influence of pH and flow rate) on permeability reduction was examined through a series of laboratory coreflooding experiments, testing for acidic (3) and alkaline (11) solutions at different flow rates (50, 100 and 200 ml/h). Permeability in continuously reduced for pH 11 to more than 50 % of initial permeability. However, at pH 3 after a slow decrease, a significant increase is observed, to more than 40 % of initial permeability. The variation is also influenced by flow rate.

Keywords: flow rate, pH, permeability, fine migration, formation damage, XRD, SEM- EDS

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1216 Permeability Prediction Based on Hydraulic Flow Unit Identification and Artificial Neural Networks

Authors: Emad A. Mohammed

Abstract:

The concept of hydraulic flow units (HFU) has been used for decades in the petroleum industry to improve the prediction of permeability. This concept is strongly related to the flow zone indicator (FZI) which is a function of the reservoir rock quality index (RQI). Both indices are based on reservoir porosity and permeability of core samples. It is assumed that core samples with similar FZI values belong to the same HFU. Thus, after dividing the porosity-permeability data based on the HFU, transformations can be done in order to estimate the permeability from the porosity. The conventional practice is to use the power law transformation using conventional HFU where percentage of error is considerably high. In this paper, neural network technique is employed as a soft computing transformation method to predict permeability instead of power law method to avoid higher percentage of error. This technique is based on HFU identification where Amaefule et al. (1993) method is utilized. In this regard, Kozeny and Carman (K–C) model, and modified K–C model by Hasan and Hossain (2011) are employed. A comparison is made between the two transformation techniques for the two porosity-permeability models. Results show that the modified K-C model helps in getting better results with lower percentage of error in predicting permeability. The results also show that the use of artificial intelligence techniques give more accurate prediction than power law method. This study was conducted on a heterogeneous complex carbonate reservoir in Oman. Data were collected from seven wells to obtain the permeability correlations for the whole field. The findings of this study will help in getting better estimation of permeability of a complex reservoir.

Keywords: permeability, hydraulic flow units, artificial intelligence, correlation

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1215 Evaluation of Re-mineralization Ability of Nanohydroxyapatite and Coral Calcium with Different Concentrations on Initial Enamel Carious Lesions

Authors: Ali Abdelnabi, Nermeen Hamza

Abstract:

Coral calcium is a boasting natural product and dietary supplement which is considered a source of alkaline calcium carbonate, this study is a comparative study, comparing the remineralization effect of the new product of coral calcium with that of nano-hydroxyapatite. Methodology: a total of 35 extracted molars were collected, examined and sectioned to obtain 70 sound enamel discs, all discs were numbered and examined by scanning electron microscope coupled with Energy Dispersive Analysis of X-rays(EDAX) for mineral content, subjected to artificial caries, and mineral content was re-measured, discs were divided into seven groups according to the remineralizing agent used, where groups 1 to 3 used 10%, 20%, 30% nanohydroxyapatite gel respectively, groups 4 to 6 used 10%, 20%, 30% coral calcium gel and group 7 with no remineralizing agent (control group). All groups were re-examined by EDAX after remineralization; data were calculated and tabulated. Results: All groups showed a statistically significant drop in calcium level after artificial caries; all groups showed a statistically significant rise in calcium content after remineralization except for the control group; groups 1 and 5 showed the highest increase in calcium level after remineralization. Conclusion: coral calcium can be considered a comparative product to nano-hydroxyapatite regarding the remineralization of enamel initial carious lesions.

Keywords: artificial caries, coral calcium, nanohydroxyapatite, re-mineralization

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1214 Enhancing Protein Incorporation in Calcium Phosphate Coating on Titanium by Rapid Biomimetic Co-Precipitation Technique

Authors: J. Suwanprateeb, F. Thammarakcharoen

Abstract:

Calcium phosphate coating (CaP) has been employed for protein delivery, but the typical direct protein adsorption on the coating led to low incorporation content and fast release of the protein from the coating. By using bovine serum albumin (BSA) as a model protein, rapid biomimetic co-precipitation between calcium phosphate and BSA was employed to control the distribution of BSA within calcium phosphate coating during biomimetic formation on titanium surface for only 6 h at 50 oC in an accelerated calcium phosphate solution. As a result, the amount of BSA incorporation and release duration could be increased by using a rapid biomimetic co-precipitation technique. Up to 43 fold increases in the BSA incorporation content and the increase from 6 h to more than 360 h in release duration compared to typical direct adsorption technique were observed depending on the initial BSA concentration used during co-precipitation (1, 10, and 100 microgram/ml). From X-ray diffraction and Fourier transform infrared spectroscopy studies, the coating composition was not altered with the incorporation of BSA by this rapid biomimetic co-precipitation and mainly comprised octacalcium phosphate and hydroxyapatite. However, the microstructure of calcium phosphate crystals changed from straight, plate-like units to curved, plate-like units with increasing BSA content.

Keywords: biomimetic, Calcium Phosphate Coating, protein, titanium

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1213 The Impact of Foliar Application of the Calcium-Containing Compounds in Increasing Resistance to Blue Mold on Apples

Authors: Masoud Baghalian, Musa Arshad

Abstract:

In order to investigate the effect of foliar application of calcium chloride on the resistance of fruits such as Red and Golden Lebanese apple varieties to blue mold, a split plot experiment in time and space, based on accidental blocks, with three replications under foliar application were done (Control, one in a thousand, two in thousands) and the results of the variance analysis showed that there is a significant difference between the levels of foliar and variety at 5% level and between time, there is significant difference in interaction of variety × time and three way interaction of foliar×variety×time, at 1% level. The highest resistance to the blue mold disease in foliar application was observed at two in thousands calcium (calcium chloride) level.

Keywords: apple, blue mold, foliar calcium, resistance

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1212 Study of the Formation Mechanism of Dipalmitoylphosphatidylcholine Liposomes and Calcium Ion Complexes

Authors: T. Mdzinarashvili, M. Khvedelidze, E. Shekiladze, S. Chinchaladze, M. Mdzinarashvili

Abstract:

The study of the possible interaction between calcium ions and lipids is of great importance for the studies of complexes of calcium drug-carrying nanoparticles. We prepared calcium-containing complex liposomes from Dipalmitoylphosphatidylcholine (DPPC) lipids and studied their thermodynamic properties. In calorimetric studies, we determined that the phase transition temperature of these complexes is close to 420 C. It was shown that both hydrophobic and hydrophilic connections take part in the formation of calcium nanoparticles. We were interested in hydrophilic bonds represented by hydrogen bonds. We have shown that these hydrogen bonds are formed between the phospholipid heads, and the main contributor is the oxygen atoms in the phosphoric acid residues. In addition, based on the amount of heat absorbed during the breaking of hydrogen bonds formed between calcium-containing nanoparticle complexes, it can be concluded that the hydrogen atoms in the head of DPPC lipids form hydrogen bonds between P=O and P-O groups of phosphate. The energy of heat absorption measured by the calorimeter is of the order obtained by breaking the hydrogen bonds we have specified. Thus, we conclude that our approach to the model of liposome formation from lipids is correct. As for calcium atoms - due to the fact that it is present in the form of positive ions in the liposome, they will connect only with negatively charged phosphorus ions.

Keywords: DPPC, liposomes, calcium, complex nanoparticles

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1211 Modeling of the Pores Form Influence on the Hydraulic Resistance of Membranes and Their Permeability

Authors: Zhanat Umarova

Abstract:

Until the present time, modeling of the pores form influence on the hydraulic resistance of membranes and their permeability has not been analyzed. The aim of the given work is the theoretical consideration of the issue on the productivity of polymer membranes with the profile pores and determination of the optimum form of pores.

Keywords: modeling, polymer membranes, permeability, pore’s density

Procedia PDF Downloads 359
1210 Development of In Situ Permeability Test Using Constant Discharge Method for Sandy Soils

Authors: A. Rifa’i, Y. Takeshita, M. Komatsu

Abstract:

The post-rain puddles problem that occurs in the first yard of Prambanan Temple are often disturbing visitor activity. A poodle layer and a drainage system has ever built to avoid such a problem, but puddles still didn’t stop appearing after rain. Permeability parameter needs to be determined by using more simple procedure to find exact method of solution. The instrument modelling were proposed according to the development of field permeability testing instrument. This experiment used proposed Constant Discharge method. Constant Discharge method used a tube poured with constant water flow. The procedure were carried out from unsaturated until saturated soil condition. Volumetric water content (θ) were being monitored by soil moisture measurement device. The results were relationship between k and θ which drawn by numerical approach Van Genutchen model. Parameters θr optimum value obtained from the test was at very dry soil. Coefficient of permeability with a density of 19.8 kN/m3 for unsaturated conditions was in range of 3 x 10-6 cm/sec (Sr= 68 %) until 9.98 x 10-4 cm/sec (Sr= 82 %). The equipment and testing procedure developed in this research was quite effective, simple and easy to be implemented on determining field soil permeability coefficient value of sandy soil. Using constant discharge method in proposed permeability test, value of permeability coefficient under unsaturated condition can be obtained without establish soil water characteristic curve.

Keywords: constant discharge method, in situ permeability test, sandy soil, unsaturated conditions

Procedia PDF Downloads 348
1209 Effects of Egg Yolk Peptide on the Retardation of Bone Growth Induced by Low-Calcium Diets

Authors: Kang-Hyun Leem, Myung-Gyou Kim, Hye Kyung Kim

Abstract:

Eggs have long been an important contributor to the nutritional quality of the human, and recognized as a very valuable source of proteins for human nutrition. Egg yolk is composed of various important chemical substances for human health. Growth means not only the increase of body weight but also the elongation of height and the enlargement of each organ's anatomical and morphological size. A calcium shortage causes the growth retardation on the body growth. In this study, we examined the therapeutic effects of egg yolk peptide (EYP) on the retardation of the longitudinal bone growth induced by low-calcium diet (0.05%) in adolescent rats. Low calcium diets were administrated for 15 days. During the last five days, calcium and/or vitamin D and/or EYP were administrated. The body weights, longitudinal bone growth rates, the heights of growth plates, and bone morphogenetic protein (BMP)-2 and insulin-like growth factor (IGF)-1 expressions were measured using histochemical analysis. Low calcium diets caused the significant reduction in body weight gains and the longitudinal bone growth. The heights of growth plates and the expressions of BMP-2 and IGF-1 showed the impairment of body growth as well. Calcium and/or vitamin D administration could not significantly increase the longitudinal bone growth. However, calcium, vitamin D, and EYP administration significantly increased the bone growth, the growth plate height, and BMP-2 and IGF-1 expressions. These results suggest that EYP enhances the longitudinal bone growth in the calcium and/or vitamin D deficiency and it could be a promising agent for the treatment of children suffering from malnutrition.

Keywords: egg yolk peptide, low-calcium diet, longitudinal bone growth, morphogenetic protein-2, insulin-like growth factor-1, vitamin D

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1208 Oil Displacement by Water in Hauterivian Sandstone Reservoir of Kashkari Oil Field

Authors: A. J. Nazari, S. Honma

Abstract:

This paper evaluates oil displacement by water in Hauterivian sandstone reservoir of Kashkari oil field in North of Afghanistan. The core samples of this oil field were taken out from well No-21st, and the relative permeability and fractional flow are analyzed. Steady state flow laboratory experiments are performed to empirically obtain the fractional flow curves and relative permeability in different water saturation ratio. The relative permeability represents the simultaneous flow behavior in the reservoir. The fractional flow approach describes the individual phases as fractional of the total flow. The fractional flow curve interprets oil displacement by water, and from the tangent of fractional flow curve can find out the average saturation behind the water front flow saturation. Therefore, relative permeability and fractional flow curves are suitable for describing the displacement of oil by water in a petroleum reservoir. The effects of irreducible water saturation, residual oil saturation on the displaceable amount of oil are investigated through Buckley-Leveret analysis.

Keywords: fractional flow, oil displacement, relative permeability, simultaneously flow

Procedia PDF Downloads 348