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Evaluation of blasting patterns using operational research models

Monjezi M., Farzaneh F., Asadi A.

Archives of Mining Sciences

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2013

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Vol. 58, no. 3

881--892

EN

Blasting is one of the most important operations, which has a great technical and economical effect on the mining projects. Criteria such as fragmentation (operation ultimate objective) and ground vibration, flyrock, airblast, etc. (operation side effects) should be considered in the assessment of blasting operation. A suitable pattern should be able to provide both reasonable (required) fragmentation and blasting side effects. In order to evaluate blasting performance, operational research models such as multi attribute decision making technique (MADM) can be applied. Technique for order preference by similarity to an ideal solution (TOPSIS), a branch of MADM, is a strong method for pattern ranking. The other quantitative method which is applied in the evaluation of systems’ efficiency is data envelopment analysis (DEA) model. In this paper, an attempt has been made to develop a new hybrid MADM model for selecting the most appropriate blasting pattern in Chadormalu iron mine, Iran. In this regard, DEA method was utilized to select the efficient blast patterns thereafter TOPSIS was used to recognize the most suitable pattern amongst the selected patterns by DEA method. It was concluded that the patterns J, G and B are the most appropriate patterns for blasting operations in the Chadormalu iron mine.

PL

Prace strzałowe to jedne z kluczowych operacji w znacznym stopniu determinujące efektywność ekonomiczną wielu projektów górniczych. W planowaniu prac strzałowych uwzględnić należy podstawowe kryteria, takie jak rozdrobnienie skał (ostateczny cel operacji), wibracje podłoża, występowanie rozrzutu skał, i podmuchów powietrza (efekty uboczne). Odpowiedni harmonogram prac zapewnić powinien zarówno odpowiedni poziom rozdrobnienia (wymiary brył) jak i ograniczenie skutków ubocznych prac. Dla oceny skuteczności prac strzałowych zastosować można modele badań operacyjnych, np. modele oparte o wielokryterialną technikę decyzyjną MADM, a technika ustalania kolejności preferowanych rozwiązań oparta o podobieństwo do rozwiązania idealnego (TOPSIS), wywodząca się z MADM, jest skuteczną metodą ustalania rankingu wzorców. Inną metodą ilościową stosowaną do oceny efektywności systemów jest metoda analizy danych DEA. W niniejszym artykule dokonano próby opracowania hybrydowego modelu MADM do wyboru najbardziej korzystnego planu prac strzałowych w kopalni rud żelaza Chadormalu, w Iranie. W ramach badań wykorzystano metodę DEA do wyboru skutecznego planu prac strzałowych, następnie zastosowano podejście TOPSIS dla rozpoznania najbardziej odpowiedniego wzorca spośród tych wybranych przy pomocy metody DEA. Stwierdzono, że wzorce oznaczone jako J, G i B są najodpowiedniejsze do zastosowania przy pracach strzałowych prowadzonych w kopalni rud żelaza Chadormalu.

2

Synthesis and characterization of Ni-Si mixed oxide nanocomposite as a catalyst for carbon nanotubes formation

Pasha M. A., Fakhroueian Z., Shafiekhani A., Vesaghi M. A., Farzaneh F.

Materials Science Poland

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2011

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Vol. 29, No. 2

144--151

EN

Ni-Si mixed oxide nanocomposite was prepared by co-precipitation method with Ni(NO3)2 ź 6H2O and tetraethylorthosilicate (TEOS) at pH = 10.5 under reflux condition for 6 days. It was then used as a catalyst for the formation of carbon nanotubes (CNTs) by CVD procedure. Characterization of the catalyst and the CNTs was carried out using X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The results showed that Ni-Si mixed oxides nanorods with the average diameter of 3 to 4 nm play a key role in CNTs formation.

3

Template Assisted Growth of Molybdenum Oxide Nanocrystals Through Hydrothermal Process

Farzaneh F., Najafi M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 9

1523-1528

EN

Rod shaped MoO3 nanocrystals were prepared from ammonium heptamolybdate tetra - hydrate (AHM) and ethylene diamine (en) as template agent in water via a hydrothermal process at 180 graduate C. The prepared nanocrystals were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The range size of nanorods are from a few nanometers (nm) to micrometers in length and 50 to 200 nm in diameter. It was also found that nanostructures of varied dimensionality such as plates and helical plates are formed using citric acid (CA), and starch as template respectively.

4

Photocatalytic Oxidation of Cyclohexene with Molecular Oxygen Using Immobilized Vitamin B12 within Nanoreactors of Al-MCM-41

Farzaneh F., Nouroozi F., Ghandi M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 1

123-130

EN

Immobilized vitamin B12 within nanoreactors of Al-MCM-41 (Vit.B12/Al-MCM-41) was used as catalyst in the photooxidation of cyclohexene with molecular oxygen in CH3CN using medium pressure mercury lamp at room temperature. It was found that 99% of cyclohexene was converted to 2-cyclohexene-1-one (70%), 2-cyclohexene-1-ol (15%) and cyclohexene oxide (15%). Details of reaction are discussed.

5

Synthesis, Characteriza tion and Epoxidation Catalytic Activity of Vanadium Sulfate Immobilized Mesoporous MCM-41

Ebrahimi Zaker Z., Farzaneh F., Ghandi M., Mohammadi N.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 3

613-619

EN

It was found that immobilized VOSO4 within nanoreactors of MCM-41 (VOSO4/MCM-41) catalyzes the epoxidation of cyclohexene, norbornene, and trans-2-hexene-1-ol with tertiary butyl hydroperoxide (TBHP) with conversion of 89 to 99% and selectivity of 80 to 100%.

6

Eco-friendly Synthesis of ZnO Nanorods in Water Using Acetylacetone as Template

Farzaneh F., Faal Hamedan N.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 8

1513--1517

EN

Nanocrystals of ZnO were prepared by microwave irradiation in water using Zn(II) acetate and acetylacetone (acac) as template. The ZnO obtained nanorods with hexagonal (wurtzite) structure were characterized by X-ray power diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), UV-vis absorption and FTIR spectroscopy.