INSIGHT INTO THE GROWTH MECHANISM OF WS2 NANOTUBES IN THE SCALED-UP FLUIDIZED-BED REACTOR

NANO ◽  
2009 ◽  
Vol 04 (02) ◽  
pp. 91-98 ◽  
Author(s):  
A. ZAK ◽  
L. SALLACAN-ECKER ◽  
A. MARGOLIN ◽  
M. GENUT ◽  
R. TENNE
Keyword(s):  
Mechanical Behavior ◽  
Fluidized Bed ◽  
Growth Mechanism ◽  
Large Scale ◽  
Analytical Techniques ◽  
Fluidized Bed Reactor ◽  
Crystalline Order ◽  
Catalyst Free ◽  
Insight Into

The growth mechanism of WS2 nanotubes in the large-scale fluidized-bed reactor is studied in greater detail. This study and careful parameterization of the conditions within the reactor lead to the synthesis of large amounts (50–100 g/batch) of pure nanotubes, which appear as a fluffy powder, and (400–500 g/batch) of nanotubes/nanoplatelets mixture (50:50), where nanotubes usually coming in bundles. The two products are obtained simultaneously in the same reaction but are collected in different zones of the reactor, in a reproducible fashion. The characterization of the nanotubes, which grow catalyst-free, by a number of analytical techniques is reported. The majority of the nanotubes range from 10 to 50 micron in length and 20–180 nm in diameter. The nanotubes reveal highly crystalline order, suggesting very good mechanical behavior with numerous applications.

Some applications of electron beam microanalysis techniques in VLSI process evaluation

1983 ◽  
Vol 41 ◽  
pp. 160-161
Author(s):  
Simon Thomas
Keyword(s):  
Integrated Circuits ◽  
Process Evaluation ◽  
Large Scale ◽  
Technology Development ◽  
Analytical Techniques ◽  
Successful Implementation ◽  
Analysis Of Failures ◽  
Characterization Of Materials ◽  
Circuits Vlsi

Trends in the technology development of very large scale integrated circuits (VLSI) have been in the direction of higher density of components with smaller dimensions. The scaling down of device dimensions has been not only laterally but also in depth. Such efforts in miniaturization bring with them new developments in materials and processing. Successful implementation of these efforts is, to a large extent, dependent on the proper understanding of the material properties, process technologies and reliability issues, through adequate analytical studies. The analytical instrumentation technology has, fortunately, kept pace with the basic requirements of devices with lateral dimensions in the micron/ submicron range and depths of the order of nonometers. Often, newer analytical techniques have emerged or the more conventional techniques have been adapted to meet the more stringent requirements. As such, a variety of analytical techniques are available today to aid an analyst in the efforts of VLSI process evaluation. Generally such analytical efforts are divided into the characterization of materials, evaluation of processing steps and the analysis of failures.

Influence of Seeding Conditions on Initial Biofilm Development during the Startup of Anaerobic Fluidized Bed Reactors

1989 ◽  
Vol 21 (4-5) ◽  
pp. 157-165 ◽  
Author(s):  
F. Ehlinger ◽  
J. M. Audic ◽  
G. M. Faup
Keyword(s):  
Fluidized Bed ◽  
Future Development ◽  
Protein Concentration ◽  
Specific Activity ◽  
Fluidized Bed Reactor ◽  
Fluidized Bed Reactors ◽  
Support Material ◽  
Biofilm Development ◽  
Initial Biofilm

The characterization of the biofilm of an anaerobic fluidized-bed reactor was completed under standard conditions. The distribution of the fixed protein concentration depended on the level in the reactor. The protein concentration reached 1520 µg.g−1 of support at the top of the reactor and only 1200 µg.g−1 at the bottom after 504 hours of operation but the specific activity of the biofilm was 33×10−4 µM acetate.h−1.mg−1 proteins at the bottom and only 26×10−4 µM.h−1.mg−1 at the top. The efficiency of a fluidized bed reactor and the composition of the biofilm changed with an increase of the pH from 7 to 8.5 during the seeding of the support material. Future development of the biofilm and the specific activity of the support were affected.

Anaerobic treatment and biogas recovery for sago wastewater management using a fluidized bed reactor

2001 ◽  
Vol 44 (6) ◽  
pp. 141-147 ◽  
Author(s):  
R. Saravanane ◽  
D. V.S. Murthy ◽  
K. Krishnaiah
Keyword(s):  
Fluidized Bed ◽  
Large Scale ◽  
Fluidized Bed Reactor ◽  
Anaerobic Treatment ◽  
Solid Content ◽  
Treated Wastewater ◽  
Maximum Efficiency ◽  
Cow Dung ◽  
Wastewater Management ◽  
High Concentration

Starch manufacturing industrial units, such as sago mills, both at medium and large scale, suffer from inadequate treatment and disposal problems due to high concentration of suspended solid content present in the effluent. In order to investigate the viability of treatment of sago effluent, a laboratory scale study was conducted. The treatment of sago effluent was studied in a continuous flow anaerobic fluidized bed reactor. The start-up of the reactor was carried out using a mixture of digested supernatant sewage sludge and cow dung slurry in different proportions. The effect of operating variables such as COD of the effluent, bed expansion, minimum fluidization velocity on efficiency of treatment and recovery of biogas was investigated. The treated wastewater was analysed for recycling and reuse to ensure an alternative for sustainable water resourse management. The maximum efficiency of treatment was found to be 82% and the nitrogen enriched digested sludge was recommended for agricultural use.

Filtered model for the cold-model gas–solid flow in a large-scale MTO fluidized bed reactor

2016 ◽  
Vol 143 ◽  
pp. 369-383 ◽  
Author(s):  
Li-Tao Zhu ◽  
Le Xie ◽  
Jie Xiao ◽  
Zheng-Hong Luo
Keyword(s):  
Fluidized Bed ◽  
Large Scale ◽  
Fluidized Bed Reactor ◽  
Cold Model ◽  
Solid Flow

scholarly journals Las degradation in a fluidized bed reactor and phylogenetic characterization of the biofilm

2013 ◽  
Vol 30 (3) ◽  
pp. 521-529 ◽  
Author(s):  
L. L. Oliveira ◽  
R. B. Costa ◽  
I. K. Sakamoto ◽  
I. C. S. Duarte ◽  
E. L. Silva ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Phylogenetic Characterization

Characterization of a limestone in a batch fluidized bed reactor for sulfur retention under oxy-fuel operating conditions

2011 ◽  
Vol 5 (5) ◽  
pp. 1190-1198 ◽  
Author(s):  
Luis F. de Diego ◽  
Margarita de las Obras-Loscertales ◽  
Francisco García-Labiano ◽  
Aránzazu Rufas ◽  
Alberto Abad ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Operating Conditions

scholarly journals Fractionation and Characterization of Petroleum Asphaltene: Focus on Metalopetroleomics

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1504
Author(s):  
Fang Zheng ◽  
Quan Shi ◽  
Germain Salvato Vallverdu ◽  
Pierre Giusti ◽  
Brice Bouyssiere
Keyword(s):  
Analytical Techniques ◽  
Review Article ◽  
Polar Fraction ◽  
Present Review ◽  
Current Review ◽  
Future Work ◽  
Insight Into

Asphaltenes, as the heaviest and most polar fraction of petroleum, have been characterized by various analytical techniques. A variety of fractionation methods have been carried out to separate asphaltenes into multiple subfractions for further investigation, and some of them have important reference significance. The goal of the current review article is to offer insight into the multitudinous analytical techniques and fractionation methods of asphaltene analysis, following an introduction with regard to the morphologies of metals and heteroatoms in asphaltenes, as well their functions on asphaltene aggregation. Learned lessons and suggestions on possible future work conclude the present review article.

scholarly journals Finite element modeling of nanoindentation on an elastic-plastic microsphere

2020 ◽  
Author(s):  
Jialian Chen ◽  
Hongzhou Li
Keyword(s):  
Finite Element ◽  
Mechanical Behavior ◽  
Computational Study ◽  
Theoretical Method ◽  
Finite Element Analyses ◽  
Structured Materials ◽  
Elastic Plastic ◽  
Element Simulation ◽  
Insight Into

Abstract The understanding of the mechanical indentation on a curved specimen (e.g., microspheres and microfibers) is of paramount importance in the characterization of curved micro-structured materials, but there has been no reliable theoretical method to evaluate the mechanical behavior of nanoindentation on a microsphere. This article reports a computational study on the instrumented nanoindentation of elastic-plastic microsphere materials via finite element simulation. The finite element analyses indicate that all loading curves are parabolic curves and the loading curve for different materials can be calculated from one single indentation. The results demonstrate that the Oliver-Pharr formula is unsuitable for calculating the elastic modulus of nanoindentation involving cured surfaces. The surface of the test specimen of a microsphere requires prepolishing to achieve accurate results of indentation on a micro-spherical material. This study provides new insight into the establishment of nanoindentation models that can effectively be used to simulate the mechanical behavior of a microsphere.

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