scholarly journals The Effect of Current Supply Duration during Stepwise Electrical Sintering of Silver Nanoparticles

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1878
Author(s):  
Iksang Lee ◽  
Arif Hussain ◽  
Hee-Lak Lee ◽  
Yoon-Jae Moon ◽  
Jun-Young Hwang ◽  
...  
Keyword(s):  
Printed Electronics ◽  
Specific Resistance ◽  
High Surface ◽  
Sem Analysis ◽  
Surface Porosity ◽  
Ag Nps ◽  
Time Duration ◽  
Time Intervals ◽  
Temperature Estimation ◽  
Glass Substrates

We studied the effect of current supply duration at final-step currents during the stepwise electrical sintering of silver (Ag) nanoparticles (NPs). Ag NPs ink was inkjet-printed onto Eagle-XG glass substrates. Constant final-step currents of 0.4 and 0.5 A with various time intervals were applied to the printed samples. The final-step current of 0.5 A damaged the line at a comparatively shorter time duration. On the other hand, the lower final-step current of 0.4 A prevented the line damage at longer time durations while producing comparatively lower Ag NPs specific resistance. The minimum specific resistances of the printed samples sintered at 0.4 and 0.5 A were 3.59 μΩ∙cm and 3.79 μΩ∙cm, respectively. Furthermore, numerical temperature estimation and scanning electron microscope (SEM) analysis were conducted to elaborate on the results. The numerical temperature estimation results implied that the lower estimated peak temperature at the final-step current of 0.4 A helped prevent Ag NP line damage. The SEM micrographs suggested that a high surface porosity—caused by higher sintering peak temperatures—in the case of the 0.5 A final-step current resulted in a comparatively higher Ag NP line-specific resistance. This contribution is a step forward in the development of Ag NP sintering for printed electronics applications.

Investigation of Droplet Impinging on a Heated Porous Surface Under Various Working Conditions; A Mathematical Modeling

2021 ◽  
pp. 2150015
Author(s):  
Mohammad Azadeh ◽  
Hamidreza Khakrah
Keyword(s):  
Droplet Diameter ◽  
High Surface ◽  
Adaptive Method ◽  
Porous Surface ◽  
Droplet Temperature ◽  
Surface Porosity ◽  
Two Phase ◽  
Air Interface ◽  
Accuracy Of Results ◽  
The Impact

This study numerically investigated the behavior of a Newtonian droplet impacting a heated porous surface. In this regard, a two-phase finite volume code was used for laminar flow. The time adaptive method was applied to enhance the accuracy of results and better convergence of the solving process. Also, the dynamic grid adaptation technique was adopted to predict the liquid-air interface precisely. The results were first validated against experimental data at different Weber numbers. Then the effect of variations in the droplet temperature was investigated on the spreading factor. The obtained results revealed that the rise in droplet temperature led to an increase in the maximum spreading diameter due to the reduction in the effects of viscosity, density, and surface tension. In the next step, the effects of droplet impact on the hydrophilic and superhydrophobic surfaces with the porosities of 20–80% were evaluated. The obtained results revealed that the increase in the surface porosity caused a decrease in the droplet diameter during the impact time. Also, at high surface porosity values, the decline in the contact angle influence on the droplet dynamic behavior was observed.

Study on the Segmental Pigging Process for the Wet Gas Gathering and Transportation Pipelines of the Puguang Gas Field

2021 ◽  
Author(s):  
Wu Liu ◽  
Jianfeng Shang ◽  
Hongsong Wang ◽  
Donghui Zhao ◽  
Yu Zou
Keyword(s):  
Sulfur Content ◽  
Slug Flow ◽  
Operating Parameter ◽  
Time Duration ◽  
Time Intervals ◽  
Gas Field ◽  
Wet Gas ◽  
High Sulfur Content ◽  
Puguang Gas Field

Abstract The gathering and transportation pipeline known as Line 1 of Puguang gas field havs the characteristics of wet gathering and transportation containing high sulfur content, large drops and effusion in low-lying areas. In the process of one pigging operation on the site, the surge volume provided by the No. 1 separator in the master gas gathering station was not effectively utilized and the time intervals for the neighboring pipeline sections were too long. In this paper, we designed several pigging proposals. OLGA was applied to analyze the operating parameter changes for the gathering and transportation pipeline Line 1, which finally determined a reasonable pigging sequence. We designed and selected the "critical pigging proposal", which the time duration for the pigging operation of the seven pipeline sections was decreased to 16.91h. Guided by the "critical pigging proposal", the downstream pipeline sections will be challenged by the risks of ice blockage. The ground eddy device was improved in the article, for the purpose of draining effusions in low-lying areas in the Puguang gas field and controlling the slug flow. In addition, the application effects of the device were analyzed.

Performance Assessment of a Low Temperature Polymer Conductor for Lead-Free Soldering Processes

2014 ◽  
Vol 2014 (1) ◽  
pp. 000251-000257
Author(s):  
Steven Grabey ◽  
Samson Shahbazi ◽  
Sarah Groman ◽  
Catherine Munoz
Keyword(s):  
Low Temperature ◽  
Thick Film ◽  
Elevated Temperatures ◽  
Printed Electronics ◽  
High Reliability ◽  
Sem Analysis ◽  
Lead Free ◽  
Sac305 Solder ◽  
Soldering Process ◽  
Lead Free Solders

An increased interest in low temperature polymer thick film products has become apparent due to the rise of the printed electronics market. The specifications for these products are becoming more demanding with expectations that the low temperature products should perform at a level that is typically reserved for their high temperature counterparts; including solderability with lead free solders, high reliability and strong adhesion. Traditionally, it has only been possible to use leaded solders for soldering to polymer based thick film conductors. Over the last 15 years environmental concerns and legislation have pushed the industry towards a lead free approach. The shift to lead free solders, while beneficial, provides new challenges during processing. The high temperatures required for a lead-free soldering process yield a naturally harsher environment for polymer thick film pastes. In the past these conditions have proven too harsh for the pastes to survive. The polymer thick film discussed in this document aims to address some of these concerns for a highly reliable and easy to process polymer thick film paste. Due to the poor leaching characteristics of polymer thick films, at elevated temperatures, the predecessors of this paste typically soldered at low temperatures with leaded solders. The goal of this paper is to present a low temperature paste that is compatible with a variety of substrates and readily accepts lead-free solder. This paper will discuss a newly formulated low temperature curing (150°C – 200°C) RoHS and REACH compliant paste that shows excellent solderability with SAC305 solder. The paste was evaluated using a dip soldering method at 235°C–250°C on a variety of substrates. The data presented includes solder acceptance, adhesion data, thermal analysis and SEM analysis.

Facile Synthesis of Activated Carbon from Swamp Taro Stalk via Single Step ZnCl2 Activation

2016 ◽  
Vol 857 ◽  
pp. 475-479 ◽  
Author(s):  
M.S. Mohammed Yahya ◽  
Jeyashelly Andas ◽  
Ghani Zaidi Ab
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Total Pore Volume ◽  
Structure Type ◽  
Sem Analysis ◽  
Single Step ◽  
Bet Surface Area ◽  
Type Iv

In this work, mesoporous activated carbon with high surface area was synthesized from swamp taro stalk by single step ZnCl2 activation. The synthesized activated carbon was characterized by Na2S2O3 volumetric method, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM) and N2 adsorption-desorption analyses. Under the single step ZnCl2 activation, the registered iodine number, BET surface area, total pore volume and pore diameter were 1087.57 mgg-1, 1242.26 m2g-1, 0.73cm3g-1 and 3.72 nm respectively with yield of 25.34%. SEM analysis evidenced the well-formation of porous structure. Type IV isotherm with H2 loops obtained from N2-sorption studies indicates the ink bottles shape mesoporous network structure. This research proved the successful conversion of plant waste into high grade activated carbon.

Synthesis of Vertical ZnO Nanorods on Glass Substrates by Simple Chemical Method

2009 ◽  
Vol 5 ◽  
pp. 223-230 ◽  
Author(s):  
P. Suresh Kumar ◽  
M. Yogeshwari ◽  
A. Dhayal Raj ◽  
D. Mangalaraj ◽  
D. Nataraj ◽  
...  
Keyword(s):  
Deposition Time ◽  
Zno Nanorods ◽  
Sem Analysis ◽  
Growth Behavior ◽  
X Ray Diffraction ◽  
Zno Film ◽  
X Ray ◽  
Glass Substrates ◽  
Simple Chemical ◽  
Cbd Method

ZnO nanorods (NRs) have been synthesized by a chemical bath deposition (CBD) method on simple glass substrate that had been precoated by successive ionic layer absorption and reaction (SILAR) with a thin ZnO film. ZnO NR array was obtained by using zinc acetate and hexamethylenetetramine as aqueous solutions at optimized pH concentration and deposition time. X-ray diffraction (XRD) and SEM analysis were used to confirm the growth of ZnO nanorods. The pH and deposition time of the solution was found to influence the growth behavior of ZnO NRs. PL analysis also reflected the growth behavior of ZnO NRs.

scholarly journals High surface porosity as the origin of emissivity features in asteroid spectra

Icarus ◽  
2012 ◽  
Vol 221 (2) ◽  
pp. 1162-1172 ◽  
Author(s):  
P. Vernazza ◽  
M. Delbo ◽  
P.L. King ◽  
M.R.M. Izawa ◽  
J. Olofsson ◽  
...  
Keyword(s):  
High Surface ◽  
Surface Porosity

Fabrication of Mesoporous Cerium Dioxide Films by Cathodic Electrodeposition

2007 ◽  
Vol 7 (11) ◽  
pp. 4198-4201 ◽  
Author(s):  
Young-Soo Kim ◽  
Jin-Kyu Lee ◽  
Jae-Hoon Ahn ◽  
Eun-Kyung Park ◽  
Gil-Pyo Kim ◽  
...  
Keyword(s):  
Small Angle ◽  
Cerium Dioxide ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Cubic Phase ◽  
Tem Analysis ◽  
X Ray ◽  
Cathodic Electrodeposition ◽  
Glass Substrates ◽  
Transmission Electron

Mesoporous cerium dioxide (Ceria, CeO2) thin films have been successfully electrodeposited onto ITO-coated glass substrates from an aqueous solution of cerium nitrate using CTAB (Cetyltrimethylammonium Bromide) as a templatingagent. The synthesized films underwent detailed characterizations. The crystallinity of synthesized CeO2 film was confirmed by XRD analysis and HR-TEM analysis, and surface morphology was investigated by SEM analysis. The presence of mesoporosity in fabricated films was confirmed by TEM and small angle X-ray analysis. As-synthesized film was observed from XRD analysis and HR-TEM image to have well-crystallized structure of cubic phase CeO2. Transmission electron microscopy and small angle X-ray analysis revealed the presence of uniform mesoporosity with a well-ordered lamellar phase in the CeO2 films electrodeposited with CTAB templating.

MORPHOLOGICAL, STRUCTURAL AND OPTICAL CHARACTERIZATIONS OF Zn-DOPED CdS BUFFER LAYER ELABORATED BY CHEMICAL BATH DEPOSITION

2020 ◽  
Vol 27 (11) ◽  
pp. 2050009
Author(s):  
H. CHERIET ◽  
H. MOUALKIA ◽  
R. BARILLE ◽  
M. ZAABAT ◽  
O. MAHROUA ◽  
...  
Keyword(s):  
Chemical Bath Deposition ◽  
Sem Analysis ◽  
Phonon Modes ◽  
Zn Doping ◽  
X Ray ◽  
Force Microscopy ◽  
Glass Substrates ◽  
Atomic Force ◽  
Lower Porosity ◽  
Xrd Patterns

Zn-doped CdS layers, with various percentage ratios [Formula: see text] (= [Zn[Formula: see text]]/[Cd[Formula: see text]]%) were grown on glass substrates by chemical bath deposition (CBD). The effect of Zn-doping on different properties of CdS is studied by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy, atomic force microscopy, energy dispersive X-ray analysis and UV-visible diffuse reflectance. The XRD patterns indicated polycrystalline films with (111) orientation and the insertion of Zn does not change the crystallinity of CdS. The Raman spectra show one major peak centered around 300[Formula: see text]cm[Formula: see text] assigned to the first-order longitudinal optic (LO) phonon modes of CdS. The surface morphology visualized by AFM and SEM analysis showed the influence of the Zn-doping on the morphology of the films, the surface roughness is found to decrease from 16.5 to 8.9[Formula: see text]nm with augmenting the ratio [Formula: see text] from 0 to 6%. In regard to the SEM analysis, the increase of [Formula: see text] yielded a lower porosity of the film and voids, and the films become more homogeneous. The EDAX spectra confirmed the existence of Zn in the doped samples. The bandgap decreases from 2.44 to 2.37[Formula: see text]eV, while the transmittance increases from 76 to 86% with augmenting the ratio [Formula: see text].

Flexible Thin Film Coating by Photo-assisted Chemical Solution Process

2016 ◽  
Vol 2016 (CICMT) ◽  
pp. 000159-000161
Author(s):  
Tetsuo Tsuchiya ◽  
T. Nakajima ◽  
I. Yamaguchi ◽  
H. Matusi ◽  
T. Nakamura
Keyword(s):  
Thin Film ◽  
Power Efficiency ◽  
Printed Electronics ◽  
Solution Process ◽  
Particle Method ◽  
Film Coating ◽  
Green Technology ◽  
Oxide Thin Film ◽  
Glass Substrates ◽  
Metal Oxide Thin Film

Abstract Printed electronics is creating many new products given the benefits of the technology compared to conventional electronics, such as thinness, flexibility, cost, ease of manufacture, fast production turn around, “green” technology, power efficiency and more. For this purpose, we have developed the photo reaction of nano-particle method (PRNP) for the preparation of the patterned metal oxide thin film on organic and glass substrates. In this paper, we demonstrate the preparation of transparent conducting thin film or resister film by the PRNP process, and their properties of the obtained films. By using the combination of the two procedures, the resistivity of the film was 5.94×10−4 Ωcm. The resulting ITO film showed mobility as high as 9.99 cm2 V−1 s−1at the carrier density of 1.05 ×1021 cm−3.Also, flexible resistor thin film(RuO2) on PI substrate was prepared by ELAMOD.

Abstract P48: Factors Associated With Delay to Treatment of Aneurysmal Subarachnoid Hemorrhage (aSAH) - A Systematic Review

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Thuy Phuong Nguyen ◽  
Sabah Rehman ◽  
Christine Stirling ◽  
Ronil V Chandra ◽  
Linda Nichols ◽  
...  
Keyword(s):  
Systematic Review ◽  
Treatment Delay ◽  
Definitive Treatment ◽  
Aneurysmal Subarachnoid Haemorrhage ◽  
Time Duration ◽  
Time Intervals ◽  
Time To Treatment ◽  
Factors Associated ◽  
Hospital Factors ◽  
Delay In Treatment

Background: Delay in treatment of aneurysmal subarachnoid haemorrhage (aSAH) appears to be common, contributing to the poor outcomes of patients. We currently have limited understanding of the causes of these delays. The aim of this systematic review was to identify delays in treatment of patients with aSAH, and to identify factors associated with treatment delay. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed. We searched four electronic databases (MEDLINE, EMBASE, Web of Science, and Google Scholar) for manuscripts published from January 1998 to 2020 using pre-designated search terms and search strategy. Main outcomes were duration of delays of any time intervals from onset of aSAH to definitive treatment and/or factors related to delays. Results: A total of 64 studies met study entry criteria. We identified 16 different time intervals in the pathway of aSAH patients and 17 groups of predictors to delay in treatment. Most studies measured time intervals between four major time points including time of onset, hospital admission, diagnosis, and receiving coiling or clipping. Methods to measure delay in treatment varied largely between studies, using cut-off timepoints or measured absolute time duration using mean or median. Demographic factors (age, sex, race, or socioeconomic status) were not associated with time to treatment. More severe aSAH reduced treatment delay in most studies. Pre-hospital delays (patients delay, late referral, late arrival of ambulance, being transferred between hospitals or arriving at the hospital outside of office hours) were associated with treatment delay. In-hospital factors (complication, having other procedures before definitive treatment, and type of treatment) had two-way association with treatment delay - both increasing and decreasing time to treatment. Conclusions: This review provides the first comprehensive understanding of types and predictors of delays in treatment of aSAH. There is significant opportunity to increase the comparability of aSAH time to treatment data, and to identify pre-hospital and in-hospital factors that currently delay treatment.

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