Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 17 of 17

Full-Text Articles in Entire DC Network

Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel Nov 2011

Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel

A.S. Md Abdul Haseeb

Biodiesel is currently in regular use as an alternative fuel over conventional petroleum diesel. However, corrosion of automotive materials is one of the concerns related to biodiesel compatibility issues. In addition, auto-oxidation of biodiesel can also enhance the corrosiveness of biodiesel. The present study aims to investigate inhibition effect of ethylenediamine (EDA), n-butylamine (nBA), tert-butylamine (TBA) against corrosion of cast iron. Static immersion tests in biodiesel in the presence (100 ppm) and absence of different corrosion inhibitors were carried out at room temperature for 1200 hours. At the end of the test, corrosion characteristic was investigated by weight loss measurements …


Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel Nov 2011

Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel

A.S. Md Abdul Haseeb

Biodiesel is currently in regular use as an alternative fuel over conventional petroleum diesel. However, corrosion of automotive materials is one of the concerns related to biodiesel compatibility issues. In addition, auto-oxidation of biodiesel can also enhance the corrosiveness of biodiesel. The present study aims to investigate inhibition effect of ethylenediamine (EDA), n-butylamine (nBA), tert-butylamine (TBA) against corrosion of cast iron. Static immersion tests in biodiesel in the presence (100 ppm) and absence of different corrosion inhibitors were carried out at room temperature for 1200 hours. At the end of the test, corrosion characteristic was investigated by weight loss measurements …


The Effects Of Small Metal Additions (Co,Cu,Ga,Mn,Al,Bi,Sn) On The Magnetocaloric Properties Of The Gd5ge2si2 Alloy, R D. Shull, V Provenzano, A J. Shapiro, A Fu, Michael W. Lufaso, J Karapetrova, G Kletetschka, V Mikula Aug 2011

The Effects Of Small Metal Additions (Co,Cu,Ga,Mn,Al,Bi,Sn) On The Magnetocaloric Properties Of The Gd5ge2si2 Alloy, R D. Shull, V Provenzano, A J. Shapiro, A Fu, Michael W. Lufaso, J Karapetrova, G Kletetschka, V Mikula

Michael W. Lufaso

The structural and magnetic properties of arc-melted and homogenized (1300 °C, 1 h) alloys of Gd5Ge1.9Si2X0.1 (X = Cu, Co, Ga, Mn, Al, Bi, or Sn) were investigated by powder x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and magnetometry. The addition of Cu, Ga, Mn, and Al completely eliminated the large hysteresis losses present in the undoped Gd5Ge2Si2 alloy between 270 and 330 K, broadened the magnetic entropy change ΔSm peak, and shifted its peak value from 275 to 305 K similar to that observed earlier for Gd5Ge1.9Si2Fe0.1. The addition of Bi or Sn had a negligible effect on …


Positional Control Over Nanoparticle Deposition Into Nanoholes, Moshood K. Morakinyo, Shankar B. Rananavare Aug 2011

Positional Control Over Nanoparticle Deposition Into Nanoholes, Moshood K. Morakinyo, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

Controlled deposition of metal nanoparticles (NPs) into lithographic patterned nanoholes has been a major challenge. Electrostatic attraction was employed in directing gold NPs of precise size into e-beam lithographically patterned holes. Citrate stabilized gold NPs with a net negative surface charge were deposited on a positively charged well-bottom surface generated by adsorption of long-chain amino-terminated organosilane N-(2-aminoethyl)-11-aminoundecyltrimethoxy- silane (AATMS). Scanning electron microscopy (SEM) results indicate that deposition of NPs into patterned holes is a function of deposition time and NPs concentration. Other factors affecting NP fill fraction are thickness of silane and resist layer and spacing between the nanoholes.


Improved Keratinase Production For Feather Degradation By Bacillus Licheniformis Zjuel31410 In Submerged Cultivation, Hui Ni, Qi-He Chen, Feng Chen, Ming-Liang Fu, Ya-Chen Dong, Hui-Nong Cai Jul 2011

Improved Keratinase Production For Feather Degradation By Bacillus Licheniformis Zjuel31410 In Submerged Cultivation, Hui Ni, Qi-He Chen, Feng Chen, Ming-Liang Fu, Ya-Chen Dong, Hui-Nong Cai

Publications

Optimal medium was used to improve the production of keratinase by Bacillus licheniformis ZJUEL31410, which has a promising application in the transformation of feather into soluble protein. The results of single factor design revealed that the concentration of feather at 20 g/l and the initial pH at value 8 was the best for the production of keratinase and the degradation of feather. Ammonia salt and nitrate salt strongly restricted the production of keratinase and the degradation of feather. Result of Box-Behnken design (BBD) experiment which was used to optimize concentrations of glucose, corn steep flour and K2HPO4 …


Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet R. Dokmeci, Kai-Tak Wan Jun 2011

Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet R. Dokmeci, Kai-Tak Wan

Kai-tak Wan

We report a technique to characterize adhesion of monolayered/multilayered graphene sheets on silicon wafer. Nanoparticles trapped at graphene-silicon interface act as point wedges to support axisymmetric blisters. Local adhesion strength is found by measuring the particle height and blister radius using a scanning electron microscope. Adhesion energy of the typical graphene-silicon interface is measured to be 151±28 mJ/m2. The proposed method and our measurements provide insights in fabrication and reliability of microelectromechanical/nanoelectromechanical systems.


Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet Dokmeci, Kai-Tak Wan Jun 2011

Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet Dokmeci, Kai-Tak Wan

Mehmet R. Dokmeci

We report a technique to characterize adhesion of monolayered/multilayered graphene sheets on silicon wafer. Nanoparticles trapped at graphene-silicon interface act as point wedges to support axisymmetric blisters. Local adhesion strength is found by measuring the particle height and blister radius using a scanning electron microscope. Adhesion energy of the typical graphene-silicon interface is measured to be 151±28 mJ/m2. The proposed method and our measurements provide insights in fabrication and reliability of microelectromechanical/nanoelectromechanical systems.


Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol E. Mcgruer, George G. Adams, Yan Du May 2011

Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol E. Mcgruer, George G. Adams, Yan Du

George G. Adams

We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy (SEM) demonstrates that these two rate-dependent modes can be related to brittle and ductile separation modes. The former behavior is indicative of brittle separation, whereas the latter accompanies ductile separation. Thus by monitoring the rate dependence of the pull-off force, the type of separation mode can be identified during cycling without interrupting the test …


Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol Mcgruer, George Adams, Yan Du May 2011

Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol Mcgruer, George Adams, Yan Du

Nicol E. McGruer

We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy (SEM) demonstrates that these two rate-dependent modes can be related to brittle and ductile separation modes. The former behavior is indicative of brittle separation, whereas the latter accompanies ductile separation. Thus by monitoring the rate dependence of the pull-off force, the type of separation mode can be identified during cycling without interrupting the test …


Effect Of Temperature On The Corrosion Behavior Of Mild Steel Upon Exposure To Palm Biodiesel Apr 2011

Effect Of Temperature On The Corrosion Behavior Of Mild Steel Upon Exposure To Palm Biodiesel

A.S. Md Abdul Haseeb

Recently biodiesel, as an alternative fuel is getting more significance to replace diesel fuel completely or partially. However, corrosion of automotive materials in biodiesel is a major concern as this can reduce engine life. This study aims to investigate the corrosion behavior of mild steel at three different temperatures such as room temperature, 50 and 80 °C. Static immersion tests in B0 (diesel), B50 (50% biodiesel in diesel), B100 (biodiesel) were carried out for 1200 h. At the end of the tests, corrosion characteristic was investigated by weight loss measurements and changes of the exposed metal surface. Fuels were analyzed …


Electric Field Tunable Magnetic Properties Of Lead-Free Na0.5bi0.5tio3/Cofe2o4 Multiferroic Composites, S Narendra Babu, Seong Gi Min, Leszek Malkinski Jan 2011

Electric Field Tunable Magnetic Properties Of Lead-Free Na0.5bi0.5tio3/Cofe2o4 Multiferroic Composites, S Narendra Babu, Seong Gi Min, Leszek Malkinski

Physics Faculty Publications

Lead-free multiferroic particulate composites of Na0.5Bi0.5TiO3 (NBT) and CoFe2O4 (CFO) have been synthesized by solid-state sintering method. A systematic study of structural, magnetic and magnetoelectric (ME) properties is undertaken. Structural and morphology studies carried out by x-ray diffraction and field emission scanning electron microscopy indicate formation of single phase for parent phases and presence of both phases in the composites. Magnetic properties are investigated using vibrating sample magnetometer and ferromagnetic resonance (FMR) measurements at room temperature. Strong ME coupling is demonstrated in NBT-CFO 70-30 mol% composite by an electrostatically tunable FMR field …


Interfacial Reactions Between Sn-3.5 Ag Solder And Ni-W Alloy Films Jan 2011

Interfacial Reactions Between Sn-3.5 Ag Solder And Ni-W Alloy Films

A.S. Md Abdul Haseeb

Nickel based alloys are currently being investigated in an effort to develop stable barrier films between lead free solder and copper substrate. In this study, interfacial reactions between Ni-W alloy films and Sn-3.5 Ag solder have been investigated. Ni-W alloys films with tungsten content in the range of 5.0-18.0 at.% were prepared on copper substrate by electrodeposition in ammonia citrate bath. Solder joints were prepared on the Ni-W coated substrate at a reflow temperature of 250 °C. The solder joint interface was investigated by Cross-sectional scanning electron microscopy, energy dispersive X-ray spectroscopy and electron back scatter diffraction. It has been …


Interfacial Reaction And Dissolution Behavior Of Cu Substrate In Molten Sn-3.8ag-0.7cu In The Presence Of Mo Nanoparticles Jan 2011

Interfacial Reaction And Dissolution Behavior Of Cu Substrate In Molten Sn-3.8ag-0.7cu In The Presence Of Mo Nanoparticles

A.S. Md Abdul Haseeb

Purpose - In electronic packaging, when solid copper comes in contact with liquid solder alloy, the former dissolves and intermetallic compounds (IMCs) form at the solid-liquid interface. The purpose of this paper is to study the effect of the presence of molybdenum nanoparticles on the dissolution of copper and the formation of interfacial IMC. Design/methodology/approach - Cu wire having a diameter of 250 μm is immersed in liquid composite solders at 250° up to 15 min. Composite solder was prepared by adding various amount of Mo nanoparticles into the Sn-3.8Ag-0.7Cu (SAC) solder paste. The dissolution behavior of Cu substrate is …


Microstructural Evolution Of Fine-Grained Layers Through The Firn Column At Summit, Greenland, R. Lomonaco, M. Albert, I. Baker Jan 2011

Microstructural Evolution Of Fine-Grained Layers Through The Firn Column At Summit, Greenland, R. Lomonaco, M. Albert, I. Baker

Dartmouth Scholarship

We present a microstructural characterization of fine-grained layers from the top 90 m of firn from Summit, Greenland, performed using a combination of scanning electron microscopy techniques including secondary electron imaging, energy-dispersive spectroscopy and electron backscattered patterns, and X-ray microcomputed tomography. The impurities in the firn, both soluble impurities and dust particles, were found largely in the grain interiors. Both c- and a-axis pole figures do not show strong evidence of a preferred orientation of the grains even at the bottom of the firn column. The firn structure became increasingly anisotropic with vertical alignment in the top 3 m, probably …


Relationship Of Surface Changes To Metal Leaching From Tungsten Composite Shot Exposed To Three Different Soil Types, Deborah Felt, Steven Larson, Chris Griggs, Catherine Nestler, Michelle Wynter Jan 2011

Relationship Of Surface Changes To Metal Leaching From Tungsten Composite Shot Exposed To Three Different Soil Types, Deborah Felt, Steven Larson, Chris Griggs, Catherine Nestler, Michelle Wynter

US Army Research

Physical changes that occur on the surface of fired shots due to firing and impact with soil may increase the dissolution of muniton metals. Increased metal dissolution could potentially increase metal transport and leaching, affecting metal concentrations in surface and groundwater. This research describes the relationship between the surface changes on fired tungsten–nickel–iron (94% W:2% Ni:4% Fe) composite shots and metals leaching from those shots. Tungsten composite shot was fired into, and aged in, three soil types (Silty Sand, Sandy Clay, and Silt) in mesoscale rainfall lysimeters to simulate live-fire conditions and subsequent interactions between the metals of the composite …


Fruit And Seed Morphology Of The Fumaria L. Species (Papaveraceae) Of Iran, Fatemeh Ebrahimzadeh Araii, Maryam Keshavarzi, Masoud Sheidaii, Parinaz Ghadam Jan 2011

Fruit And Seed Morphology Of The Fumaria L. Species (Papaveraceae) Of Iran, Fatemeh Ebrahimzadeh Araii, Maryam Keshavarzi, Masoud Sheidaii, Parinaz Ghadam

Turkish Journal of Botany

The macro and micro fruit and seed morphology and surface ornamentations of 21 populations of 6 Fumaria L. species were investigated using stereomicroscope and scanning electron microscopy. These data are shown to support data from the general morphology. The results indicate that the fruit and seed characters of the genus Fumaria are valuable for taxonomic applications and are useful for classification. F. officinalis show a different shape in their fruit. The close relationships are observed for F. parviflora and F. vaillantii. F. indica, as a hybrid between F. asepala and F. parviflora, shows intermediate micro-morphological features.


Failure Analysis Of Retrieved Uhmwpe Tibial Insert In Total Knee Replacement Dec 2010

Failure Analysis Of Retrieved Uhmwpe Tibial Insert In Total Knee Replacement

A.S. Md Abdul Haseeb

This study involves the failure analysis of an ultra high molecular polyethylene (UHMWPE) tibial insert from Apollo® Total Knee System, which was removed after 10. years of service from 70. years old female patient. The tibial insert was investigated by using a stereoscope, scanning electron microscope (SEM), infinite focus microscope (IFM) and energy disperse spectroscopy (EDS) to characterize the morphology and composition of the bearing surface. Differential scanning calorimetry (DSC) and Fourier transform spectroscopy (FTIR) were employed to characterize the degradation and crystallinity of the component. Gel-permeation chromatography (GPC) was used to measure the polyethylene tibial insert molecular weight. Results …