Preparation and Properties of Rigid Cross-Linked PVC Foam

2011 ◽  
Vol 311-313 ◽  
pp. 1056-1060 ◽  
Author(s):  
Ai Hua Shi ◽  
Guang Cheng Zhang ◽  
Heng Tai Pan ◽  
Zhong Lei Ma ◽  
Chen Hui Zhao
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Weight Loss ◽  
Cellular Structure ◽  
High Performance ◽  
Chemical Structure ◽  
Molding Process ◽  
Thermogravimetric Analyzer ◽  
Infrared Spectrometer ◽  
Scanning Electron

High performance rigid cross-linked PVC foam has been prepared by molding process and boiling foam process with the main materials including polyvinyl chloride paste resin (PVC), liquefied methylene bis-phenyl diisocyanate (MDI-L) and methylhexahydrophthalic anhydride (MHHPA). The chemical structure, cellular structure and thermal properties were respectively characterized by fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM), thermomechanical analyzer (TMA) and thermogravimetric analyzer (TGA). Results showed that the foam had a uniform cellular structure, and cell size was about 760μm. The glass transition temperature (Tg) was 81°C and 5% weight loss temperature (T5d) was 252°C.

The bright future of digital imaging in scanning electron microscopy

1993 ◽  
Vol 51 ◽  
pp. 768-769
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Imaging ◽  
High Speed ◽  
High Performance ◽  
Mass Storage ◽  
Analog To Digital ◽  
Central Processing ◽  
Digital Imaging Technology ◽  
Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 × 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 × 4096 resolution or greater. The two major categories of SEM systems to which digital technology have been applied are:In the analog SEM system the scan generator is normally operated in an analog manner and the image is displayed in an analog or "slow scan" mode.

scholarly journals Corrosion Inhibitive Action and Adsorption Behaviour of Justicia Secunda Leaves Extract as an Eco‐Friendly Inhibitor for Aluminium in Acidic Media

2021 ◽  
Vol 11 (5) ◽  
pp. 13019-13030
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Weight Loss ◽  
Electrochemical Impedance ◽  
Physical Adsorption ◽  
Charge Transfer Resistance ◽  
Aluminum Surface ◽  
Protective Film ◽  
Transfer Resistance ◽  
Scanning Electron

The extract of Justicia secunda (JS) leaves was investigated as an eco‐friendly corrosion inhibitor of aluminum in 0.5 M HCl using weight loss, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and scanning electron microscopy (SEM) techniques. The inhibitor concentrations used ranged from 50 to 250 ppm at 30, 40, and 50oC. Results show that Justicia secunda acts as a good inhibitor for aluminum. Its efficiency increased with increasing inhibitor concentration but decreased with increasing temperature. Maximum inhibition efficiency as high as 94.3% was found at 30°C for 250 ppm of the inhibitor with the weight loss technique. Tafel polarization results show that the extract acts as a mixed-type inhibitor. The Nyquist plots indicated decreasing double-layer capacitance and increasing charge transfer resistance on increasing JS concentration. The inhibition action occurred through the physical adsorption of the extract on the aluminum surface. The adsorption process was found to follow Langmuir adsorption isotherm. The formation of a protective film on the metal surface was confirmed by scanning electron microscopy.

scholarly journals Boosting the Adhesivity of π-Conjugated Polymers by Embedding Platinum Acetylides towards High-Performance Thermoelectric Composites

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 593 ◽  
Author(s):  
Tao Wan ◽  
Xiaojun Yin ◽  
Chengjun Pan ◽  
Danqing Liu ◽  
Xiaoyan Zhou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Conjugated Polymers ◽  
High Performance ◽  
Single Walled Carbon Nanotubes ◽  
Strong Interactions ◽  
Transmission Electron ◽  
Higher Power ◽  
Walled Carbon Nanotubes ◽  
Scanning Electron

Single-walled carbon nanotubes (SWCNTs) incorporated with π-conjugated polymers, have proven to be an effective approach in the production of advanced thermoelectric composites. However, the studied polymers are mainly limited to scanty conventional conductive polymers, and their performances still remain to be improved. Herein, a new planar moiety of platinum acetylide in the π-conjugated system is introduced to enhance the intermolecular interaction with the SWCNTs via π–π and d–π interactions, which is crucial in regulating the thermoelectric performances of SWCNT-based composites. As expected, SWCNT composites based on the platinum acetylides embedded polymers displayed a higher power factor (130.7 ± 3.8 μW·m−1·K−2) at ambient temperature than those without platinum acetylides (59.5 ± 0.7 μW·m−1·K−2) under the same conditions. Moreover, the strong interactions between the platinum acetylide-based polymers and the SWCNTs are confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements.

scholarly journals The Bright Future of Digital Imaging in Scanning Electron Microscopy

1994 ◽  
Vol 2 (4) ◽  
pp. 19-20 ◽  
Author(s):  
M.T. Postek ◽  
A.E. Vladar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Imaging ◽  
High Speed ◽  
High Performance ◽  
Mass Storage ◽  
Analog To Digital ◽  
Central Processing ◽  
Digital Imaging Technology ◽  
Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 X 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 X 4096 resolution or greater.

Preparation and Study on the Performance of Glazed Hollow Beads Thermal Insulation Materials

2013 ◽  
Vol 662 ◽  
pp. 335-338
Author(s):  
Xiao Long Li ◽  
Guo Zhong Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermal Insulation ◽  
Material Properties ◽  
Cementitious Materials ◽  
Insulation Material ◽  
Action Mechanism ◽  
Molding Process ◽  
Internal Morphology ◽  
Scanning Electron

The glazed hollow beads thermal insulation board was made of glazed hollow beads and perlite by selecting cement and fly ash as cementitious materials, and adding appropriate amount of VAE emulsion and fibers, in the compression molding process. In this paper, the influence of different dosages of perlite replacing vitrified beads, VAE emulsion and fiber on the material properties were studied. Besides, the internal morphology of the sample was observed by scanning electron microscopy, and the action mechanism of the insulation material was explored.

scholarly journals WATER JET TECHNOLOGY AND SALT TREATMENT USED FOR CARROT STICKS.

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 651f-651
Author(s):  
Yasuo Tatsumi ◽  
Alley E. Watada ◽  
Peter P. Ling
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Weight Loss ◽  
Water Jet ◽  
Nacl Solution ◽  
Salt Treatment ◽  
Textural Quality ◽  
White Tissue ◽  
Cut Surface ◽  
Scanning Electron

Water jet technology to slice carrots or salt treatment prior to slicing was studied to minimize the unappealing whitish tissue noted with carrot sticks. The water jet was a fine stream with 378,950 kPa force. Salt treatment consisted of immersing carrots in NaCl solution ranging from 0.0 to 1.0 M concentration for 3 to 20 hours. Subsequently, the carrots were sliced, stored at 5 C, and analyzed. Carrot sticks sliced with the water jet had a greater amount of white tissue than those sliced with a knife. Scanning electron microscopy showed that the water jet caused grooves on the cut surface, which exposed many layers of cells to dehydrate rapidly. The grooves probably can be minimized by increasing the speed of slicing. Salt treatments of 0.5 to 1.0 M concentration caused 3 to 10 percent weight loss when treated for 20 hours at 5 C or 3 hours at 20 C. Carrot sticks with increased weight loss had less whitish tissue and had an appearance of freshly cut sticks; however, the textural quality decreased.

scholarly journals Synthesis and Characterization Molecularly Imprinted Polymers for Analysis of Dimethylamylamine Using Acrylamide as Monomer Functional

2018 ◽  
pp. 76-84
Author(s):  
Saeful Amin ◽  
Sophi Damayanti ◽  
Slamet Ibrahim
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Size Structure ◽  
Imprinted Polymer ◽  
Morphological Form ◽  
Molecularly Imprinted ◽  
Scanning Electron

A selective separation techniques with Molecularly Imprinted Polymer (MIP) for High-Performance Liquid Chromatography (HPLC) has been developed for the assay of Dimethylamylamine (DMAA) doping compounds. Molecular imprinted polymer (MIP) is a technique to produce a polymer having the cavity due to the disposal of the templates, in which the cavity serves to recognize the molecules of the same size, structure, chemical and physical properties. The selectivity and affinity of the templates itself will increase, while the concentration value is increasing. MIP is made by DMAA as template, acrylamide as functional monomer, ethylene glycol dimethacrylate (EGDMA) as cross linking, azobisisobutyronitrile (AIBN) as the initiator and chloroform as a porogen solvent; using bulk method. The aim of research are conduct the MIP for the DMAA compound analysis, then the formed MIP is characterized by using Fourier Transform Infra Red (FTIR) and Scanning Electron Microscopy (SEM) to find out the polymer complexes formed and the morphological form of the MIP. The MIP formed then was analyzed by using High-Performance Liquid Chromatography (HPLC) to know the amount of the DMAA, the adsorption capacity, and the adsorption condition found in the MIP. The result of analysis on the content of DMAA in the MIP by using UV-Vis Spectrophotometer is 1.957 mg. Scanning Electron Microscopy (SEM) shows that the MIP has irregular and rough morphological structure; while the NIP has irregular morphology structures and smooth surfaces shape

THE EFFECT OF ALUMINA NANOPARTICLES ADDITION ON HIGH-TEMPERATURE WEAR BEHAVIOR OF INTERMETALLIC IRON ALUMINIDE PRODUCED BY THE SPARK PLASMA SINTERING PROCESS

2020 ◽  
Vol 27 (11) ◽  
pp. 2050004
Author(s):  
HAMID GHANBARI ADIVI ◽  
IMAN EBRAHIMZADEH ◽  
MORTEZA HADI ◽  
MORTEZA TAYEBI
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Weight Loss ◽  
High Temperature ◽  
Wear Behavior ◽  
Iron Aluminide ◽  
Alumina Nanoparticles ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Scanning Electron

The pure iron and aluminum powders were milled with 3[Formula: see text]wt.% and 7[Formula: see text]wt.% of alumina nanoparticles in planetary ball mill in order to produce iron aluminide by mechanical alloying technique. The resulting powder mixture was sintered after the formation of iron aluminide by spark plasma sintering (SPS) method to achieve specimens with the highest densification. SPS technique was utilized on specimens under the condition of 40[Formula: see text]MPa pressure at 950∘C for 5[Formula: see text]min. The microstructures were analyzed after sintering using scanning electron microscopy and EDS analysis. The results indicated that the aluminide iron phase has been produced at high purity. The sintered specimens were treated under hardness and density tests, and it was characterized that the specimen included 3[Formula: see text]wt.% of alumina nanoparticles had the highest microhardness. Likewise, it was revealed that the unreinforced sample had a maximum relative density. The wear behavior of specimens was performed at 600∘C. The results of weight loss showed after 1000[Formula: see text]m of wear test, the weight loss of unreinforced specimen was reduced up to 0.21[Formula: see text]g while the specimen with 3[Formula: see text]wt.% of alumina nanoparticle indicated the lowest weight loss about 0.02[Formula: see text]g. The worn surfaces were evaluated by scanning electron microscopy which indicated that the main wear mechanism at high temperature included adhesive wear and delamination.

High resolution Scanning Electron Microscopy

1989 ◽  
Vol 47 ◽  
pp. 6-7
Author(s):  
David C. Joy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
High Performance ◽  
Secondary Electron ◽  
Wide Energy Range ◽  
Wide Energy ◽  
Electron Microscopes ◽  
Electron Imaging ◽  
Scanning Electron

High resolution scanning electron microscopy is still a relatively new and unfamiliar concept because in the early days of the SEM it was expected, that secondary electron imaging would be limited to a resolution of between 5 and 10nm at best. Now, however, because of improvements in instrumentation and technique based on advances in the understanding of electron beam interactions with solids current SEMs can demonstrate spatial resolutions below 1nm, rivaling those obtained by transmission instruments.High performance scanning electron microscopes always incorporate two advanced items of instrumentation. Firstly they use field emission guns (FEGs). The high brightness, low energy spread, and small source size of the FEG makes it possible to produce an electron probe of sub-nanometer size which contains sufficient current for secondary electron imaging (i.e 10-12 amps or more) and which can maintain this performance over a wide energy range (3 to 30keV). Secondly, the new high performance instruments place the specimen within a high excitation, immersion, probe forming lens.

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