scholarly journals Current-Induced Changes of Surface Morphology in Printed Ag Thin Wires

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3288
Author(s):  
Quan Sun ◽  
Yebo Lu ◽  
Chengli Tang ◽  
Haijun Song ◽  
Chao Li ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Current Density ◽  
Flexible Substrate ◽  
Wire Surface ◽  
Flux Divergence ◽  
Thin Wires ◽  
Electrical Reliability ◽  
Induced Changes ◽  
Good Agreement ◽  
Main Factor

Current-induced changes of surface morphology in printed Ag thin wires were investigated by current stressing tests and numerical simulation. The samples were printed Ag thin wires on a flexible substrate with input and output pads. Different experimentalresults were obtainedthroughchangingthe current density after current supply and the mechanism of those phenomena were investigated by numerical simulations based on the method of atomic flux divergence. Good agreement between the simulations and experimental results was reached. It was found that electromigration was the main factor that caused the change of the surface morphology. The contribution of thermal migration can be ignored, and the Joule heating lead by the supplied current had a very significant accelerating effect on electromigration. Guidelines for effectively changing the Ag thin wire surface through providing predetermined current density was proposed, which were expected to be useful for improving the electrical reliability and lifetime of printed Ag thin wires in flexible electronic devices.

Study on Electrodeposition of Ni-Graphite Composite Coatings in Sulfamate Bath

2010 ◽  
Vol 150-151 ◽  
pp. 1546-1550 ◽  
Author(s):  
Xiang Zhu He ◽  
Xiao Wei Zhang ◽  
Xin Li Zhou ◽  
Zhi Hong Fu
Keyword(s):  
Surface Morphology ◽  
Process Parameters ◽  
Current Density ◽  
Graphite Particle ◽  
Particle Concentration ◽  
Composite Coatings ◽  
Nickel Matrix ◽  
Graphite Composite ◽  
Surface Morphologies ◽  
Sulfamate Bath

This paper presented the composite coatings of nickel with graphite particle on the aluminum substrate using a nickel sulfamate bath. Effects of graphite particle concentration on the surface morphologies of the composite coatings were investigated. The inclusion of graphite particle into metal deposits was dependent on many process parameters, including particle concentration, current density, pH and temperature. Results of SEM and XRD demonstrated that graphite particle had successfully deposited on that nickel matrix; besides, the surface morphology of coatings obtained from sulfamate bath containing 2g/L graphite particle dispersed more uniformly than the ones with higher concentration.

Surface morphology and agglutination of lectin-treated human lymphocytes and lymphoblasts

1976 ◽  
Vol 21 (3) ◽  
pp. 563-578
Author(s):  
J.H. Temmink ◽  
J.G. Collard ◽  
J. Roosien ◽  
J.F. Van den Bosch
Keyword(s):  
Cell Surface ◽  
Surface Morphology ◽  
Human Lymphocytes ◽  
Cell Type ◽  
A Cell ◽  
Human Peripheral Lymphocytes ◽  
Normal Human ◽  
Altered Cell ◽  
Induced Changes ◽  
Cell Surface Morphology

Two human lymphoblasts (Raji and EB3) and normal human peripheral lymphocytes were exposed to different concentrations of Concanavalin A and wheat germ agglutinin. The lectin-induced agglutination was determined and correlated with lectin-induced changes in the surface morphology of these cells as studied in a scanning electron microscope. Whenever the lectin induced high agglutinability in a cell type, it also invariably had a smoothing effect on the cell surface. In contrast, when cells did not agglutinate well with a certain lectin, their cell surface remained essentially rough (villous) after addition of the lectin. The correlation found between increased agglutinability and altered cell surface morphology upon treatment with certain lectins suggests that both phenomena result from one and the same process. Additional evidence for this postulate is presented.

scholarly journals NMR studies of anion-induced conformational changes in diindolylureas and diindolylthioureas

2011 ◽  
Vol 7 ◽  
pp. 1205-1214 ◽  
Author(s):  
Damjan Makuc ◽  
Jennifer R Hiscock ◽  
Mark E Light ◽  
Philip A Gale ◽  
Janez Plavec
Keyword(s):  
Conformational Changes ◽  
Chemical Shifts ◽  
Dihydrogen Phosphate ◽  
Nmr Studies ◽  
Receptor Complexes ◽  
Hydrogen Bond Interactions ◽  
Weak Binding ◽  
Oxo Anions ◽  
Induced Changes ◽  
Good Agreement

The conformational properties of 1,3-diindolylureas and thioureas were studied by a combination of heteronuclear NMR spectroscopy and quantum mechanics calculations. NOE experiments showed that the anti–anti conformer along the C7–N7α bonds was predominant in DMSO-d 6 solution in the absence of anions. Anion-induced changes in the 1H and 15N chemical shifts confirm the weak binding of chloride anions with negligible conformational changes. Strong deshielding of ureido protons and moderate deshielding of indole NH was observed upon the addition of acetate, benzoate, bicarbonate and dihydrogen phosphate, which indicated that the predominant hydrogen bond interactions occurred at the urea donor groups. Binding of oxo-anions caused conformational changes along the C7–N7α bonds and the syn–syn conformer was preferred for anion–receptor complexes. The conformational changes upon anion binding are in good agreement with energetic preferences established by ab initio calculations.

scholarly journals Radar Cross-Section Formulation of a Shell-Shaped Projectile Using Modified PO Analysis

2012 ◽  
Vol 2012 ◽  
pp. 1-9
Author(s):  
Mohammad Asif Zaman ◽  
Md. Abdul Matin
Keyword(s):  
Differential Geometry ◽  
Cross Section ◽  
Current Density ◽  
Surface Current ◽  
Radar Cross Section ◽  
Analysis Procedure ◽  
Physical Optics ◽  
Surface Current Density ◽  
Filtering Method ◽  
Good Agreement

A physical optics based method is presented for calculation of monostatic Radar Cross-Section (RCS) of a shell-shaped projectile. The projectile is modeled using differential geometry. The paper presents a detailed analysis procedure for RCS formulation using physical optics (PO) method. The shortcomings of the PO method in predicting accurate surface current density near the shadow boundaries are highlighted. A Fourier transform-based filtering method is proposed to remove the discontinuities in the approximated surface current density. The modified current density is used to formulate the scattered field and RCS. Numerical results are presented comparing the proposed method with conventional PO method. The results are also compared with published results of similar objects and found to be in good agreement.

THE EFFECT OF PREPARED PARAMETERS ON THE MICROSTRUCTURE OF ELECTRODEPOSITED NANOCRYSTALLINE NICKEL COATING

2004 ◽  
Vol 11 (04n05) ◽  
pp. 433-442 ◽  
Author(s):  
C. Y. DAI ◽  
Y. PAN ◽  
S. JIANG ◽  
Y. C. ZHOU
Keyword(s):  
Grain Size ◽  
Surface Morphology ◽  
Current Density ◽  
Crystal Orientation ◽  
Nickel Coating ◽  
Pulse Frequency ◽  
Lattice Parameter ◽  
Nanocrystalline Nickel ◽  
Peak Current Density ◽  
Peak Current

The nanocrystalline nickel coating was synthesized by pulse-jet electrodeposition from modified Watts bath. Pulse and jet plating was employed to increase the deposition current density, decrease diffusion layer, increase the nucleation rate and in this case the prepared method would result in fine-grained deposits. Transmission and scanning electron microscopy and X-ray diffraction (XRD) were used to study the microstructure, the surface morphology, the crystal preferred orientation and the variety of the lattice parameter respectively. The influence of pulse parameters, namely peak current density, the duty cycle and pulse frequency on the grain size, surface morphology, crystal orientation and microstructure was studied. The results showed that with increasing peak current density, the deposit grain size was found to decrease markedly in other parameters at constant. However, in our experiment it was found that the grain size increased slightly with increasing pulse frequency. For higher peak current density, the surface morphology was smoother. The crystal orientation progressively changed from an almost random distribution to a strong (111) texture. This means that the peak current density was the dominated parameter to effect the microstructure of electrodeposited nanocrystalline nickel coating. In addition, the lattice parameter for the deposited nickel is calculated from XRD and it is found that the calculated value is less than the lattice parameter for the perfect nickel single crystal. This phenomenon is explained by the crystal lattice mismatch.

CATHODE SURFACE CHANGES IN THE PRESENCE OF GELATIN DURING ELECTRODEPOSITION OF COPPER

1943 ◽  
Vol 21b (6) ◽  
pp. 125-132 ◽  
Author(s):  
W. Gauvin ◽  
C. A. Winkler
Keyword(s):  
Grain Size ◽  
Current Density ◽  
Copper Sulphate ◽  
Cathode Surface ◽  
Active Area ◽  
Cathode Polarization ◽  
Active Centres ◽  
Main Factor ◽  
Surface Changes

Measurements of the cathode polarization during electrodeposition of copper from acid copper sulphate solutions indicate that introduction of gelatin into the electrolyte decreases the area of the cathode available for deposition, or active area, owing to adsorption of gelatin on the active centres. This decrease in area causes an increase in the true current density, with a resulting increase in cathode polarization, the former being assumed the main factor in causing an increase in the rate of nuclear formation and decrease in grain size.

Crystal Orientation and Surface Morphology of Sono-Electroplated Zinc Film from Alkali Zincate Bath

2009 ◽  
Vol 79-82 ◽  
pp. 1743-1746
Author(s):  
Atsushi Chiba
Keyword(s):  
Surface Morphology ◽  
Current Efficiency ◽  
Compressive Stress ◽  
Diffusion Layer ◽  
Current Density ◽  
Crystal Orientation ◽  
Shearing Stress ◽  
Thickness Of Diffusion Layer ◽  
Zincate Solution

Zn plated on Cu plate from 0.65 mol/dm3 alkali zincate solution in 8 mol/dm3 KOH bath Electrolysis was carried out as current density of 10 - 100 mA/cm2. The sonication was prepared 40 kHz. The current efficiency was 76.1 % at 10 mA/cm2 in 0.10 mol/dm3 zincate and 100 % in 0.15 mol/dm3 zincate at 50 mA/cm2. The current efficiency and thickness of diffusion layer affected with the agitation of micro-jet. Surface of film was smooth and dense as particle crushed down with the shockwave pressure. (112) plane moved horizontally to <113> direction under the compressive stress or shearing stress.

scholarly journals Mechanical properties of NiTi and CuNiTi wires used in orthodontic treatment. Part 2: Microscopic surface appraisal and metallurgical characteristics

2014 ◽  
Vol 19 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Marco Abdo Gravina ◽  
Cristiane Canavarro ◽  
Carlos Nelson Elias ◽  
Maria das Graças Afonso Miranda Chaves ◽  
Ione Helena Vieira Portella Brunharo ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Test Methods ◽  
Chemical Compositions ◽  
Wire Surface ◽  
Morphologic Characteristics ◽  
Fracture Region ◽  
Traction Test ◽  
Niti Wires ◽  
Electronic Microscope

OBJECTIVE: This research aimed at comparing the qualitative chemical compositions and the surface morphology of fracture regions of eight types of Nickel (Ni) Titanium (Ti) conventional wires, superelastic and heat-activated (GAC, TP, Ormco, Masel, Morelli and Unitek), to the wires with addition of copper (CuNiTi 27oC and 35oC, Ormco) after traction test. METHODS: The analyses were performed in a scanning electronic microscope (JEOL, model JSM-5800 LV) with EDS system of microanalysis (energy dispersive spectroscopy). RESULTS : The results showed that NiTi wires presented Ni and Ti as the main elements of the alloy with minimum differences in their composition. The CuNiTi wires, however, presented Ni and Ti with a significant percentage of copper (Cu). As for surface morphology, the wires that presented the lowest wire-surface roughness were the superelastic ones by Masel and Morelli, while those that presented the greatest wire-surface roughness were the CuNiTi 27oC and 35oC ones by Ormco, due to presence of microcavity formed as a result of pulling out some particles, possibly of NiTi. 4 The fracture surfaces presented characteristics of ductile fracture, with presence of microcavities. The superelastic wires by GAC and the CuNiTi 27oC and the heat-activated ones by Unitek presented the smallest microcavities and the lowest wire-surface roughness with regard to fracture, while the CuNiTi 35oC wires presented inadequate wire-surface roughness in the fracture region. CONCLUSION: CuNiTi 35oC wires did not present better morphologic characteristics in comparison to the other wires with regard to surfaces and fracture region.

Effect of Current Density on the Composition and Mechanical Properties of Cr1-xAlxN Coating by Ion Arc Plating

2012 ◽  
Vol 557-559 ◽  
pp. 1971-1974
Author(s):  
Cheng Xi Wang ◽  
Ji Hua Peng ◽  
Xian Wen Liang ◽  
Jun Tian
Keyword(s):  
Mechanical Properties ◽  
Surface Morphology ◽  
Current Density ◽  
Adhesion Force ◽  
Atomic Ratio ◽  
Pure Metal ◽  
Metal Target ◽  
Micro Hardness ◽  
Al Content ◽  
Maximum Value

The Cr1-xAlxN coatings were deposited onto M2 tool steel using ion arc plating technique. The effect of current density on the surface morphology and mechanical properties of TiN/CrAlN coating was made. It was found that adjusting the pure metal target currents is not only to change the metal atomic ratio, but also to influence the surface morphology, their hardness and adhesion. The micro hardness Hv increases almost linearly with Al content of the coating in this study, and the Cr0.41Al0.59N coating reaches Hv 2950. The adhesion force between the coating and the substrate reaches maximum value 55N, when the [Al]/[Al+Cr] ratio is 0.44.

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