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1

Customized porous implants by additive manufacturing for zygomatic reconstruction

Moiduddin K., Al-Ahmari A., Al Kindi M., Nasr E. S. A., Mohammad A., Ramalingam S.

Biocybernetics and Biomedical Engineering

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2016

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Vol. 36, no. 4

719--730

EN

Background: Moderate to severe facial esthetic problems challenge the surgeons to discover alternate ways, to rehabilitate the patients using customized porous designs. Porous metal implants are available for over 30 years, but the pore architecture, is constantly changing to improve the stability and longevity of the implant. Objective: To evaluate a customized porous implant produced from electron beam melting and to restore the zygomatic functionality. Methods: Two customized zygomatic reconstruction implants-bulk and porous, are designed based on the bone contours and manufactured using state of art-electron beam melting technology. The two designed implants are evaluated based on strength, weight and porosity for the better osseointegration and rehabilitation of the patient. Results: Porous structures due to their light weight, low volume and high surface area provided better specific strength and young's modulus closer to the bone. Microscopic and CT scanning confirmed that the EBM produced porous structures are highly regular and interconnected without any major internal defects. Conclusions: The customized porous implants satisfies the need of lighter implants with an adequate mechanical strength, restoring better functionality and esthetic outcomes for the patients.

2

Trace elements in scalp hair of leukaemia patients

Khuder A., Bakir M. A., Hasan R., Mohammad A., Habil K.

Nukleonika

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2014

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Vol. 59, No. 3

111--120

EN

The aim of this study was to determine the concentration of Fe, Ni, Cu, Zn and Pb in scalp hair of leukaemia patients and healthy volunteers, using the optimised XRF method. Leukaemia hair samples were classifi ed corresponding to type, growth and age of the participants. The results showed that the studied trace elements (TEs) in both of leukaemia and control groups were positively skewed. In comparison with the control group, lower Fe, Cu, Zn and Pb and higher of Ni medians were found in all studied leukaemia patients. The median rank obtained by Mann–Whitney U-test revealed insignifi cant differences between the leukaemia patients subgroups and the controls. An exact probability (α < 0.05) associated with the U-test showed signifi cant differences between medians in leukaemia patients and controls groups for Pb (lymphatic/control, acute/control), Cu (lymphatic/control, chronic/control), Ni (lymphatic/control, chronic/control) and Fe (chronic/control). Very strong positive and negative correlations (r > 0.70) in the scalp hair of control group were observed between Ni/Fe-Ni, Cu/Fe-Cu, Zn/Fe-Zn, Pb/Fe-Pb, Cu/Ni-Zn/Ni, Cu/Ni-Pb/Ni, Zn/Ni-Pb/Ni, Zn/Fe-Zn/Cu, Pb/Ni-Ni and Ni/Fe-Pb/Ni, whereas only very strong positive ratios in the scalp hair of leukaemia patients group were observed between Ni/Fe-Ni, Cu/Fe-Cu, Zn/Fe-Zn and Pb/Fe-Pb, all correlations were signifi cant at p < 0.05. Other strong and signifi cant correlations were also observed in scalp hair of both groups. Signifi cant differences between grouping of studied TEs in all classifi ed leukaemia groups and controls were found using principal component analysis (PCA). The results of PCA confi rmed that the type and the growth of leukaemia factors were more important in element loading than the age factor.

3

Development a new classification for assessing the coal mine mechanization

Mehdi H. S., Reza M., Mohammad A., Khalokakaei R., Akhyani M.

Archives of Mining Sciences

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2013

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Vol. 58, no. 1

217--226

EN

The coal mine mechanization is important to achieve optimum quality and maximum efficiency of coal production. Mechanization is an objective that can result in significant cost reductions and higher levels of profitability for underground mines. The potential of coal mine mechanization depends on some important factors Such as seam inclination and thickness, geological disturbances, seam floor conditions and roof conditions. These factors should be considered in coal mine mechanization analysis. In this study, the new classification was developed with the respect to the mentioned factors. Using this system the coal seam mechanization index (CSMi) of several types of coal seams was evaluated and classified into five categories; very good, good, medium, low and very low. As a case study, the mechanization of the Takht coal seams in Golestan area of Iran was investigated using this new classification system. The results show a low potential for mechanization in most of the Takht coal seams.

PL

Mechanizacja prac w kopalniach węgla jest konieczna dla osiągnięcia maksymalnej wydajności produkcji i uzyskania węgla najwyższej jakości. Mechanizacja jest celem, który skutkować będzie znacznym obniżeniem kosztów oraz zwiększeniem poziomu rentowności produkcji w kopalniach podziemnych. Możliwości mechanizacji w kopalniach uzależnione są od szeregu ważnych czynników, takich jak nachylenie i miąższość złoża, obecność zaburzeń struktury geologicznej a także warunki stropowe i spągowe. Czynniki te koniecznie uwzględnić należy w analizach możliwości mechanizacji pracy kopalni. W pracy tej przedstawiono nową klasyfikację opartą o wyżej wymienione czynniki. W oparciu o przyjęte podejście, obliczony został wskaźnik mechanizacji dla złoża węgla i następnie zastosowany został do analiz. Na jego podstawie wyodrębniono pięć kategorii złóż węglowych w kontekście możliwości mechanicznego urabiania: bardzo dobre, dobre, średnie, niskie i bardzo niskie. Jako studium przypadku przedstawiono analizę złoża węglowego Takht w regionie Golestan w Iranie, w oparciu o zaproponowany nowy system klasyfikacji. Wyniki analizy wskazują, że większość złóż w regionie Takht stwarza niewielkie możliwości dla zastosowania mechanizacji.

4

Major, minor, and trace elements in whole blood of patients with different leukemia patterns

Khuder A., Bakir M. A., Solaiman A., Issa H., Habil K., Mohammad A.

Nukleonika

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2012

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Vol. 57, No. 3

389-399

EN

The elemental sensitivity method for X-ray fluorescence analysis was applied to determine S, Cl, K, Ca, Fe, Cu, Zn, Br, and Rb in the whole blood of leukemia patients and healthy volunteers. Leukemia samples were classified according to type, growth, and age of participants. Student’s t-test results showed that, the mean concentration of the studied elements was significantly lower in leukemia patients than that in controls. Strong mutual correlations (r greather than 0.50) in the whole blood of leukemia patients were observed between S-Ca, K-Fe, K-Ca, Fe-Zn, K-Zn, K-Rb, Fe-Rb, Zn-Rb, S-Cl, S-K, Ca-Fe, Cl-Ca, and Ca-Rb; whereas, S-K, S-Ca, S-Cl, Cl-K, Cl-Ca, Fe-Zn, Zn-Rb, Fe-Rb, K-Fe, and Zn-Br exhibited strong relationships (r greather than 0.50) in the whole blood of controls, all were significant at p less than 0.05. Significant differences between grouping of studied elements in the control group and all classified leukemia groups, except younger age-group, were obtained using principal component analysis. The study indicated appreciably different patterns of element distribution and mutual relationships in the whole blood of leukemia patients in comparison with controls.

5

In - house preparation and evaluation of Tc-99m-HIG kit for detection of infection in AIDS patients

Bakir M. A., Mansour R., Mohammad A., Habil K., Yassine T.

Nukleonika

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2012

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Vol. 57, No. 1

117-124

EN

99mTc-HIG can be used for early detection of inflammation and infection foci especially in immunodeficiency patients. The present study involves in-house preparation and evaluation of human immunoglobulin-hydrazinonicotinic acid (HIG-HYNIC) kit to be labeled with 99mTc. In this indirect labeling method, the structure and biological activity of the protein can be maintained. The kit consists of two vials A and B, the vial A contains 2 mg of HIG-HYNIC, and the vial B contains 10 mg of tricine and 1 mg of stannous chloride dihydrate (SnCl2.2H2O). The results revealed that the lyophilized kits were stable for at least 10 months, and showed a high quality from the points of physical, chemical, radiochemical and biological purities, and its validity for human injection. The labeling yield of HIG-HYNIC compound exceeded 98%. The application of the prepared kit was experimentally illustrated in animal models with artificially induced inflammatory lesions after E. coli injection into rat leg muscle. The biodistribution and imaging studies in rats have shown good localization in infected muscle (T) in comparison to the normal muscle (M) 4 and 24 h after injection. Ratios of 17 and 18 were achieved 4 and 24 h post injection, respectively. The results of biodistribution of 99mTc-HIG in human and initial clinical evaluation show that this agent is a good radiopharmaceutical for infection imaging.

6

Specific separation of thiamine from hydrophilic vitamins with aqueous dioxane on precoated silica TLC plates

Mohammad A., Zehra A.

Acta Chromatographica

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2008

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Vol. 20, no. 4

637-642

EN

Specific separation of thiamine hydrochloride from riboflavin, nicotinic acid, calcium D-pantothenate, pyridoxine hydrochloride, cyanocobalamin, and ascorbic acid has been achieved on commercial precoated silica gel 60F 254 TLC plates with dioxane-water 1:1 (υ/υ ) as mobile phase. The spots were visualized under UV light. The effect of impurities (metal cations and inorganic anions) on the chromatography of thiamine hydrochloride was examined. The detection limit for thiamine hydrochloride was 0.09 µg per spot and the relative standard deviation of the R F value of thiamine hydrochloride in five analyses was 14.99%. The applicability of the method to the identification of thiamine in pharmaceutical formulations was also tested.

7

Silica gel thin-layer chromatographic separation of cetylpyridinium chloride (CPC) from polyoxyethylene (20) sorbitan monolaurate (Tween-20)

Mohammad A., Bhawani S. A.

Acta Chromatographica

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2007

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No. 18

238-248

EN

Thin-layer chromatography of eleven cationic and non-ionic surfactants has been performed on silica gel layers with tetrahydrofuran (THF)- containing aqueous mobile phases. The mobile phase tetrahydrofuran–water 6:4 was identified as best for mutual separation of cetylpyridinium chloride (CPC) and polyoxyethylene (20) sorbitan monolaurate (Tween-20). The effect of the nature of the adsorbent (silica gel, alumina, or kieselguhr) on the mobility of the surfactants was examined and the comparative efficiency of each adsorbent was evaluated. The effect of metal cations as foreign substances on the mutual separation of CPC and Tween-20 was also examined. Limits of detection were determined for CPC and Tween-20 and semi quantitative determination of CPC was also attempted.

8

Cetylpyridinium chloride micelle-mediated mutual separation of zinc, cadmium, and mercury ions by thin-layer chromatography

Mohammad A., Agrawal V., Shahab H.

Acta Chromatographica

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2007

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No. 19

185-196

EN

Cationic surfactant-mediated systems containing different concentrations of cetylpyridinium chloride have been used as mobile phases in thin-layer chromatographic separation of metal cations on silica layers. The effect of surfactant concentrations below and above the critical micelle concentration (CMC) on the retention behaviour of metal ions was examined. The best TLC system for rapid mutual separation of Zn2+, Cd2+, and Hg2+ was unmodified silica as stationary phase and 5% aqueous cetylpyridinium chloride as mobile phase. The effects of pH (acidity or basicity), inorganic electrolytes (the acetate, formate, chloride, bromide, and carbonate of sodium and the chloride and nitrate of calcium), and organic compounds (urea) in the cetylpyridinium chloride solution on the mobility and separation efficiency of Zn2+, Cd2+, and Hg2+ were assessed. The limits of detection for these metal cations were also determined. The method is well suited to identification and separation of Hg2+, Zn2+, and Cd2+ from synthetically prepared ores, for example cinnabar (HgS), zinc blende (ZnS), and greenoekite (CdS), and from hydroxide sludge.

9

Use of a glutamic acid-containing aqueous-organic mobile phase for on-plate separation, detection, and identification of cationic and non-ionic surfactants by thin-layer chromatography

Mohammad A., Shahab H.

Acta Chromatographica

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2006

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No. 17

272-291

EN

A new thin-layer chromatographic system comprising silica gel G as stationary-phase and a three-component mobile phase, 0.1 M glutamic acid–methanol–acetone, 1:1:1 (v/v), has been found to be highly suitable for separation and identification of cationic and non-ionic surfactants. The experimental conditions were optimized to achieve differential migration of the surfactants. In addition to achieving separation of some important cationic and non-ionic surfactants on laboratory-prepared silica gel layers and on silica gel HPTLC plates, tetradecyltrimethylammonium bromide (TTAB) has been successfully separated from Triton X-100 (TX-100) in the presence of heavy metal cations. The method has been used for identification of TTAB and TX-100 in saline water, river water, and domestic waste water. Limits of detection were determined for TTAB and TX-100. TLC coupled with spectrophotometry was used for quantitative estimation of TTAB after preliminary separation from TX-100. The effects on separation of TTAB from TX-100 of sample pH, polarity of the alcohol in the mobile phase, nature of the amino acid in the mobile phase, and the presence of alumina, kieselguhr, or cellulose in the silica layer have also been examined.

10

Use of micellar anionic surfactant solutions with added carbohydrates as mobile phases in thin-layer chromatography of heavy metal cations. Separation of mixtures of aluminium(III), manganese(II), and chromium(VI)

Mohammad A., Shahab H.

Acta Chromatographica

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2005

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No. 15

192-205

EN

A new thin-layer chromatographic system comprising silica gel "G" as stationary phase and a micellar solution of sodium dodecyl sulphate (0.01 M) with added maltose (0.5 M) in 7:3 (v/v) ratio has been identified as most favourable for identification and separation of mixtures of alumi-nium(III), manganese(II), and chromium(VI). The presence of the carbo-hydrate enhances the separation efficiency of micellar solution of anionic surfactant (i.e. SDS). The experimental conditions were optimized to achieve separation of aluminium, manganese, and hexavalent chromium under dif-ferent experimental conditions of sample pH, layer material composition, presence of foreign substances in the sample, nature of the polar head group of the surfactant, and the nature of the carbohydrate in the micellar mobile phase. The limits of detection and semiquantitative determination of the separated metal cations were also determined.

11

Simultaneous separation of nitroaniline isomers with a water-in-oil microemulsion

Mohammad A., Hina S.

Acta Chromatographica

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2005

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No. 15

238-246

EN

Thin-layer chromatography of nineteen amines has been performed on silica gel layers with a water-in-oil microemulsion (sodium dodecyl sul-phate + water + heptane + n-pentanol, 8.0 g + 8.0 mL + 160.0 mL + 25.0 mL) as mobile phase. The effect of the basicity of the amines on their RF values was examined. The proposed thin layer chromatographic method was used to separate isomers of nitroaniline from their mixture.

12

Reversed-phase chromatography of amines, phenols, and metal cations on silica layers impregnated with tributyl phosphate, using surfactant-mediated mobile phases

Mohammad A., Jabeen N.

Acta Chromatographica

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2003

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No. 13

135-153

EN

The analytical potential of tri-n-butyl phosphate (TBP) as impreg-nant in the thin-layer chromatographic separation of mixtures of amines, phenols, or metal ions has been investigated. Silica gel impregnated with 0.001 M TBP as stationary phase and an aqueous micellar solution (0.01 M) of CTAB, a cationic surfactant, as mobile phase was found to be the best chromatographic system for achieving important separations of metal cations (e.g. Cr3+ from Cr6+, Fe3+ from Mn2+ and Cr6+, VO2+ from Mn2+ and Cr6+) and phenols (e.g. o-cresol from m-cresol, m-aminophenol from o-aminophenol) from their mixtures. An aqueous solution (8.3 × 10-6 M) of the non-ionic surfactant, Brij-35 proved suitable for achieving good separations of amines (e.g. p-dimethylaminobenzaldehyde from L-tryptophan, p-dimethylaminobenzaldehyde from indole) on silica layers impregnated with 0.001 M TBP. The effect of metal cations on the separation of amines and phenols was examined, as was the effect of amines and phenols on the separation of metal ions. The effect of foreign substances on the separation of analytes was marginal.

13

Novel mobile phase for separation of Cr6+ from Cr3+ and associated heavy metal cations by high-performance thin-layer chromatography

Mohammad A., Sirwal Y. H.

Acta Chromatographica

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2003

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No. 13

117-134

EN

Eleven heavy metal cations have been chromatographed on silica gel high-performance thin-layer chromatography plates with pure organic, mixed organic, and mixed aqueous-organic mobile phases. Mobile phases such as methanol-dimethylamine, 8:2 (v/v), and methanol-dimethylamine -formic acid, 8:8:2 (v/v), were found most suitable for rapid separation and identification of mixtures of Cr6+ and Cr3+ and of Cr6+, Ni2+, and Co2+, respectively. The effect of impurities such as inorganic ions, phenols, and surfactants on the separation of Cr6+ and Cr3+ was examined. Mutual separation of Cr6+, Ni2+, and Co2+ was investigated at different sample solution pH. The limit of detection for Ni2+, Co2+, Cu2+, and Pb2+ on HPTLC plates was evaluated and semiquantitative determination of Cr6+ and Ni2+ by spot-area measurement was attempted. The proposed method was successfully used for identification of Cr6+, Cr3+, Ni2+, and Co2+ and for mutual separation of Cr6+ from Cr3+ and of Cr6+ from Ni2+ and Co2+ from a variety of industrial wastewater samples.

14

Use of cationic micellar mobile phases in normal-phase TLC for enhanced selectivity in the separation of transition metal ions: simultaneous separation of mixtures of zinc, nickel, mercury, and cadmium or manganese cations

Mohammad A., Agrawal V.

Acta Chromatographica

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2002

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No. 12

177-188

EN

Thin-layer chromatography of five transition metal cations has been performed on silica gel layers with micellar solutions of N,N-cetyltrimethyl-ammonium bromide (CTAB) as mobile phases. The effect of surfactant concentrations below and above the critical micellar concentration (CMC) on the retention behaviour of metal ions was examined. The effect of organic and inorganic additives on the mobility and separation efficiency of the metal ions was also assessed. The best TLC system for rapid separation of mixtures of Zn2+, Ni2+, Hg2+, and Cd2+ or Mn2+ was plain silica as stationary phase and 50 mM aqueous CTAB as mobile phase. CTAB buffered at moderate pH (e.g. pH 3.4) was found suitable for separating mixtures of these metal ions. Semiquantitative determination of Ni2+ by spot-area measurement was also attempted. The proposed method was used for separation and identification of zinc, nickel, mercury, and manganese or cadmium from drag-out nickel-plating solution and from a sludge sample containing their hydroxides.

15

Thin layer chromatography of inorganic ions on blended inorganic ion-exchangers with tributyl phosphate-formic acid as mobile phase

Mohammad A., Yousuf R., Hamid Y.

Acta Chromatographica

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2001

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No. 11

171-182

EN

The chromatographic behaviour of some cations and anions has been examined on layers prepared from 1:9 mixtures of a synthetic inorganic ion-exchanger (stannic arsenate or tin(IV) molybdosilicate, synthesized under different experimental conditions) with silica gel, alumina, or cellulose, with tri-n-butyl phosphate-formic acid as mobile phase. Several binary separations of analytical interest were achieved on these blended adsorbent phases. The effect of pH on the separation of IO3- from NO2- and BrO3- in the presence of cations was also examined. Quantitative determination of IO3- on mixed stannic arsenate-alumina, 1:9, was also performed success-fully.

16

Thin layer chromatographic separation and recovery of gold and silver from secondary sources

Mohammad A., Syed S., Sharma L. M., Syed A. A.

Acta Chromatographica

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2001

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No. 11

183-195

EN

Thin-layer chromatography coupled with spectrophotometry and titrimetry has been used to separate Au3+ and Ag+ from accompanying metal ions. The method has been used to recover gold and silver from secondary sources. Silica gel G layers developed with aqueous N-cetyl-N,N,N-trimethylammonium bromide solution (1.2 mM) and alumina G layers developed with aqueous ammonium sulphate solution (2.5 M) were found most suitable for the separation of Au3+ and Ag+ respectively. The recovery of Au3+ from printed circuit boards and Ag+ from a variety of silver-containing spent materials was approximately 91-95%.

17

Quaternary separation of some transition metal chlorosulphates on mixed adsorbent layers with water as mobile phase. Quantitative determination of nickel chlorosulphate

Mohammad A., Najar P. A.

Acta Chromatographica

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2001

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No. 11

154-170

EN

The analytical potential of double-distilled water for the separation of transition metal chlorosulphates is described. Nickel chlorosulphate is well separated from manganese, iron, copper, or zinc chlorosulphates on mixed silica gel-cellulose (2:1 w/w) adsorbent layers. Several stationary phase-mobile phase combinations were tested to identify suitable chromato-graphic systems for analysis of metal chlorosulphates. Quaternary separations, e.g. Mn-Fe-Ni-Cu and Mn-Fe-Ni-Zn have been achieved. The effect of anionic species on the mobility and separation of metal chlorosulphates has been examined. Nickel as its chlorosulphate has been quantitatively determined after TLC separation from Mn, Fe, and Zn chlorosulphates on mixed silica gel-cellulose layers with double-distilled water as mobile phase.

18

Thin-layer chromatographic separation of phenols with buffered mobile phases containing cationic surfactants

Mohammad A., Anwar S., Iraqi E., Khan I. A.

Acta Chromatographica

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2000

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No. 10

195-213

EN

The retention behaviour of nineteen phenols has been examined on plain and ethylenediamine tetraacetic acid (EDTA)-impregnated silica gel layers developed with buffered solutions of cetyltrimethylammonium bromide (CTAB). The effect of CTAB concentration and the nature of other additives (alcohols of different carbon-chain length and acetonitrile) on the RF value (or mobility) of the phenols was studied. Among the additives investigated, 5% methanol was found most suitable. Good separations of phenols were possible with 1% CTAB in 50:50:8 (v/v) 0.04 M boric acid–0.04 M phosphoric acid–0.24 M NaOH as mobile phase. Some important separations were achieved experimentally both on plain silica and on EDTA-impregnated layers.

19

Detection, identification and separation of certain heavy metals on silica gel - supported tin(IV) arsenosilicate layers

Mohammad A., Anwar S., Iraqi E.

Chemia Analityczna

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1999

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Vol. 44, No. 2

195-200

EN

Separation of metal ions was carried out on thin layers of silica gel, mixed silica gel -tin(IV) arsenosilicate, and the latter impregnated with tributylaJnine in methanol. Good results were obtained using mobile phases containing methanol. The RF values for 13 ions were given as well as examples of their separation.

PL

Rozdzielanie jonów metali prowadzono na cienkich warstwach żelu krzemionkowego, mieszanego żelu krzemionkowego i arsenokrzemianu cyny(IV). oraz na takich war-stwach impregnowanych roztworami tributyloaminy w metanolu. Dobre wyniki uzyska-no stosując fazy ruchome zawierające kwas mrówkowy. Podano wartości RF dla 13 jonów metali, oraz przykłady rozdzielania ich mieszanin.

20

Identification of Hg2+ and its separation from UO22+ and Fe3+ on impregnated silica gel layers by use of formic acid-sodium chloride mobile phases

Mohammad A., Ajmal M., Anwar S.

Acta Chromatographica

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1999

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No. 9

113-122

EN

The chromatographic behaviour of some inorganic pollutants has been studied on thin layers of silica gel impregnated with potassium thiocyanate and developed with formic acid–sodium chloride mobile phases. The effect of surfactants, halides and oxyanions on the separation of Hg2+ from UO22+ and Fe3+ was examined. The method was used to identify Hg2+, Pb2+, Cd2+, and Zn2+ in synthetic sludge.