Strength evaluation of air cured, cement treated peat with blast furnace slag

Kalantari, Behzad Techno-Press 2011 Geomechanics & engineering Vol.3 No.3

This article describes laboratory research done on strength evaluations for stabilized samples made of tropical fibrous peat. The stabilizing agents used were ordinary Portland cement (OPC) as binding agent and blast furnace slag (BFS) as additive. Stabilized samples were tested for their strength through unconfined compressive strength (UCS) and California bearing ratio (CBR). Different dosage rates of OPC and BFS were used in trial and error experiments for the most effective combination for stabilized peat samples that were at their natural moisture content. Stabilized trial samples were air cured for 90 days. After detecting the most effective dosage rate in the trial samples, their values were used to prepare CBR samples at their optimum moisture content (OMC). CBR samples were then air cured from 1 to 90 days and tested under un-soaked and soaked conditions. The most effective dosage rate for the stabilized peat samples was found to be close to when 75% for OPC and 25% of BFS per total weight of OPC, and BFS. As an example, if 11.25% OPC, and 3.75% BFS are mixed with peat and compacted at their OMC and air cured for 90 days, stabilized peat will have an increase in CBR of 0.8% to 45 % for un-soaked and 20% for soaked conditions.

Compressibility behaviour of peat reinforced with precast stabilized peat columns and FEM analysis

Kalantari, Behzad,Rezazade, Reza K. Techno-Press 2015 Geomechanics & engineering Vol.9 No.4

Researches have been done to discover ways to strengthen peat soil deposits. In this model study, fibrous peat that is the most compressible types of peat has been reinforced with precast peat columns stabilized with ordinary Portland cement and polypropylene fibres. Rowe cell consolidation tests as well as plate load tests (PLTs) were conducted on various types of test samples to evaluate the strength and deformation of untreated peat and peat reinforced by various types of columns. PLTs were conducted in a specially designed and fabricated circular steel test tank. The compression index ($C_c$) and recompression index ($C_r$) of fibrous peat samples reduced considerably upon use of precast columns. Also, PLT results confirmed the results obtained from Rowe cell tests. Use of polypropylene fibres added to cement further decreased ($C_c$) and ($C_r$) and increased load bearing capacity of untreated peat. Finite element method (FEM) using Plaxis 3D was carried out to evaluate the stress distributions along various types of tested samples and also, to compare the deformations obtained from FEM analysis with the actual maximum deformations found from PLTs. FEM results indicate that most of the induced stresses are taken on the upper portion of tested samples and reach their maximum values below the loading plate. Also, a close agreement was found between actual deformation values obtained from PLTs and values resulted from FEM analysis for various types of tested samples.

The effect of gender on willingness to pay for mass customised running shoes

Kalantari Hassan Daronkola,Johnson Lester W,Perera Chamila R. 한국마케팅과학회 2021 Journal of Global Fashion Marketing Vol.12 No.2

We investigate whether gender and different levels of customisation have a significant effect on consumers’ willingness to purchase mass customised running shoes. An online panel survey was utilised to collect data from 353 Australian adults who wear running shoes at least once a month. Three attributes – degree of customisation, price, and delivery time were utilised in the data analysis to explore willingness to pay for customised shoes. Informed by conjoint analysis and t-tests, the study makes a significant theoretical contribution by extending the understanding of inconveniences of mass customisation from the perspective of customers’ willingness across genders. It is found that for women, degree of customisation and delivery time are the most important attributes, while for men, price and degree of customisation are the more crucial attributes. Female customers are more willing to purchase the product than male customers. The study addresses the research gap that is how differently females and males who usually have different sensory perceptions respond to masscustomised products. Further, the study provides valuable strategic insights for both manufacturers and marketers to cater fragmented consumer markets through mass customisation by identifying subtle differences in customer readiness among their target group of customers.

THREE CONVEX HULL THEOREMS ON TRIANGLES AND CIRCLES

Kalantari, Bahman,Park, Jong Youll The Honam Mathematical Society 2014 호남수학학술지 Vol.36 No.4

We prove three convex hull theorems on triangles and circles. Given a triangle ${\triangle}$ and a point p, let ${\triangle}^{\prime}$ be the triangle each of whose vertices is the intersection of the orthogonal line from p to an extended edge of ${\triangle}$. Let ${\triangle}^{{\prime}{\prime}}$ be the triangle whose vertices are the centers of three circles, each passing through p and two other vertices of ${\triangle}$. The first theorem characterizes when $p{\in}{\triangle}$ via a distance duality. The triangle algorithm in [1] utilizes a general version of this theorem to solve the convex hull membership problem in any dimension. The second theorem proves $p{\in}{\triangle}$ if and only if $p{\in}{\triangle}^{\prime}$. These are used to prove the third: Suppose p be does not lie on any extended edge of ${\triangle}$. Then $p{\in}{\triangle}$ if and only if $p{\in}{\triangle}^{{\prime{\prime}}$.

A computational intelligence scheme for prediction of interfacial tension between pure hydrocarbons and water

Kalantari Meybodi, Mahdi,Shokrollahi, Amin,Safari, Hossein,Lee, Moonyong,Bahadori, Alireza Elsevier 2015 Chemical engineering research & design Vol.95 No.-

<P><B>Abstract</B></P> <P>Interfacial tension plays a major role in many disciplines of science and engineering. Complex nature of this property has restricted most of the previous theoretical studies on thermophysical properties to bulk properties measured far from the interface. Considering the drawbacks and deficiencies of preexisting models, there is yet a huge interest in accurate determination of this property using a rather simple and more comprehensive modeling approach. In recent years, inductive machine learning algorithms have widely been applied in solving a variety of engineering problems. This study introduces least-square support vector machines (LS-SVM) approach as a viable and powerful tool for predicting the interfacial tension between pure hydrocarbon and water. Comparing the model to experimental data, an excellent agreement was observed yielding the overall squared correlation coefficient (<I>R</I> <SUP>2</SUP>) of 0.993. Proposed model was also found to outperform when compared to some previously presented multiple regression models. An outlier detection method was also introduced to determine the model applicability domain and diagnose the outliers in the gathered dataset. Results of this study indicate that the model can be applied in systems over temperature ranges of 454.40–890°R and pressure ranges of 0.1–300MPa.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Least square support vector machine (LS-SVM) algorithm is used to estimate Interfacial tension (IFT). </LI> <LI> The model has been developed and tested using several hundreds series of the data. </LI> <LI> Validity of the presented models has been evaluated by utilizing several statistical parameters. </LI> <LI> The predictions of the developed models results are in excellent agreement with data. </LI> </UL> </P>

Evaluation of the Genotoxicity of Cadmium Chloride in Mice Using the Micronucleus Test

Kalantari, Heybatullah,Akhbari, Arash,Elliott, Simon Korean Environmental Mutagen Society 2002 한국환경성돌연변이·발암원학회지 Vol.22 No.4

In order to determine the safety of chemicals and pharmaceutical products, various methods can be used to evaluate the toxicity. In this study the genotoxic effect of the widely used industrial chemical, cadmium chloride, was assessed using the micronucleus test in peripheral blood of mice. The presence of micronucleated reticulocytes by microscopic observation following acridine orange staining indicated a potential genotoxic effect. The genotoxicity of intraperitoneally (i.p.) administered cadmium chloride (0.5, 1, 2 mg/kg) appeared to be dose dependent, with the maximum tolerated dose (MTD) found to be 2 mg/kg. Compared to the negative control (saline), cadmium chloride (2 mg/kg) exhibited statistically significant genotoxic potential (P<0.05) but was found to be less than the positive control of mitomycin C (0.5 mg/kg) and was not statistically significant compared to historical negative controls (P>0.05).

Application of Iranian Medicinal Plants to the Treatment of Liver Injury.

Kalantari, H.,Arzi, A.,Haghperast, M.,Chang, Il-Moo Korean Society of ToxicologyKorea Environmental Mu 1997 Toxicological Research Vol.13 No.3

Matricaria Chammomillal L., Foemiculum Vulgare mill, and Plantago Psylium L. have been screened for their hepato protective activities against liver damge induced by $CCl_4$ intoxication in mice. Hydroalcoholic extractions (2:8) of herbal drugs were concentrated in vacuo and concentrated crude extracts of Matrica Chammomilla L. and Foeniculum Vulgare mill were orally administered at doses of 100 mg/kg, 200 mg/kg, 400 mg/kg, and 800 mg/kg. Plantago Psyllium was given at doses of 50 mg/kg, 100 mg/kg, 200 mg/kg, and 400 mg/kg. Liver protective activities of these herbs were determined after administration of $CCl_4$ Liver size, serum enzyme activities, sleeping time, and histopatology of the liver were examined one hour after administration of $CCl_4$. ALT and AST activities, liver weight and sleeping time decreased in groups that received 400 mg/kg of Matricaria Chammomilla L. or Foeniculum Vulgare. Histological investigation showed significant increase in hepatic cell regeneration and reduction in liver injury. The group that received 100 mg/kg Plantago Psylium showed liver protection but protection was not significant in other doses.

Peat stabilization using cement, polypropylene and steel fibres

Kalantari, Behzad,Prasad, Arun,Huat, Bujang B.K. Techno-Press 2010 Geomechanics & engineering Vol.2 No.4

This article describes a laboratory research on stabilizing tropical peat using ordinary Portland cement (OPC) as a binding agent, and polypropylene and steel fibres as chemically inert additives. California bearing ratio (CBR) and unconfined compressive strength (UCS) tests were carried out to evaluate the increase in the strength of the stabilized samples compacted at their optimum moisture contents and air cured for up to 90 days. The results show that the UCS values of stabilized peat samples increased by as high as 748.8% by using OPC (5%), polypropylene fibres (0.15%), and steel fibres (2%). The CBR values of the samples stabilized with OPC (5%), polypropylene fibres (0.15%), and steel fibres (4%) showed an increase of as high as 122.7%. The stabilized samples showed a shrinkage in volume upon air curing and this shrinkage was measured by an index called, volume shrinkage index (VSI). The highest VSI recorded was 36.19% for peat without any additives; and the minimum was 0% for the sample containing 30% OPC, 0.15% polypropylene fibres and 2% steel fibres. The technique of stabilizing peat with OPC, polypropylene and fibres, coupled with air curing, appears to be cost-effective compared with other frequently used techniques.

Experimental and Numerical Study of a Seismic Rotating Mass Damper (RMD) in an Isolated Floor

Afshin Kalantari,Reihane Shafie Panah 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.4

Negative stiffness has shown a capable characteristic in reduction of seismic response of structures. In this paper a passive Rotating Mass Damper (RMD) with negative stiffness characteristic, which was conceptually introduced in an earlier study, has been employed experimentally and numerically on an isolated floor to protect the building content during strong ground motions. The equipment was assumed as a rigid block on the isolated floor. The RMD devices force results indicate the negative stiffness characteristic of the damper. It was also observed that the RMD could increase the natural period of the system up to 50 percent without increasing the mass or reducing the stiffness. A numerical model of a seven storey building was employed to investigate the seismic response of the isolation floor in fourth storey. Two RMD models with different specifications and a viscous damper providing 10 percent of critical damping were applied in the study. Seven ground motion records were selected from PEER ground motion database. The time history analysis results indicate that RMD dampers show acceptable performance in terms of reducing both acceleration up to 40% and displacement responses up to 68% simultaneously in comparison with the viscous damper under the applied ground motions. The model was also analyzed employing seven artificial seismic waves. The results in this part also show the capability of the damper model in generating negative stiffness characteristics and a successful performance during excitation.

Effect of chromium and boron incorporation methods on structural and catalytic properties of hierarchical ZSM-5 in the methanol-to-propylene process

Neda Kalantari,Maged F. Bekheet,Parastoo Delir Kheyrollahi Nezhad,Jan O. Back,Ali Farzi,Simon Penner,Nagihan Delibas,Sabine Schwarz,Johannes Bernardi,Dariush Salari,Aligholi Niaei 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.111 No.-

We introduced chromium and boron into the hierarchical structure of ZSM-5 by following an incipientwet impregnation and hydrothermal synthesis approach to enhance the performance of the catalystsin the methanol-to-propylene process. Crystal structure, preferred orientation, and crystal symmetry ofsynthesized zeolites were discussed using Rietveld refinement and revealed that all synthesized zeolitescrystallized in a monoclinic structure, whereas the boron-incorporated sample exhibited an orthorhombicsymmetry. Large-scale defect-free single-crystalline structures of hierarchical zeolite created by CTABand F127 mesoporogens are confirmed by electron microscopy and magic angle spinning nuclear magneticresonance (MAS NMR). The formation of surface metal oxides and extra-framework metal oxidescaused changes in the electronic structure of the components as visible in Si 2p and O 1s spectra. The predominantpresence of OH groups and the higher Cr (VI) /Cr (III) ratio account for the better performanceof impregnated chromium-ZSM-5 especially in the production of light olefins. The introduction of boronby impregnation further preserved the preferred growth orientation, hierarchical structure with highcrystallinity and caused surface acidity changes in favor of increasing propylene selectivity to 67% witha propylene/ethylene ratio of close to 8.