Electroactive Polymers Based on Novel Ionomers

Aerospace ◽  
2003 ◽  
Author(s):  
Barbar J. Akle ◽  
Mike Hickner ◽  
Donald J. Leo ◽  
James E. McGrath
Keyword(s):  
Chemical Properties ◽  
Base Material ◽  
Ionic Concentration ◽  
Sensors And Actuators ◽  
Ionic Polymer ◽  
Precise Control ◽  
Ionic Groups ◽  
Improved Performance ◽  
And Performance ◽  
Physical And Chemical

A majority of research on ionic polymer transducers has used Nafion™ as the base material. Varying the physical and chemical properties of Nafion is difficult, which limits the understanding and development of ionic transducers. In this study we investigate a novel class of polymers called BPSH (sulfonated poly(arylene ether sulfone)s). The polymers are synthesized by the direct polymerization of sulfonated monomers. This synthetic scheme affords precise control of the amount and the location of ionic groups along the polymar backbone. These polymers differ from Nafion™ in two major ways. First, the concentration of ionic groups on a mass basis is almost double that of standard Nafion™, 1.51 meq/g for BPSH-30 versus 0.91 meq/g for Nafion™ 1100. Also, the backbone of the BPSH copolymers is much stiffer than Nafion, which affords a higher modulus material. Both of these factors, ion content and modulus, are expected to affect the performance of polymer-based actuators. Another ionomer characterized is the PATS (poly(arylene thiother sulfone)s) which is similar to BPSH. For both polymers we are varying the ionic concentration, stiffness, and water content. Those variations are fostering the understanding of operating concepts of ionic transducers, especially the correlation between ionic transducers, especially the correlation between ionic concentration and performance. Experiments on BPSH-35 demonstrate improved performance as compared to Nafion™ They provide larger strain per unit volt, larger force generated, and larger bandwidth. The novel polymers are characterized as sensors and actuators.

Nanocrystals: The Preparation, Precise Control and Application Toward the Pharmaceutics and Food Industry

2018 ◽  
Vol 24 (21) ◽  
pp. 2425-2431 ◽  
Author(s):  
Cao Wu ◽  
Zhou Chen ◽  
Ya Hu ◽  
Zhiyuan Rao ◽  
Wangping Wu ◽  
...  
Keyword(s):  
Food Industry ◽  
Chemical Properties ◽  
Preparation Methods ◽  
Precise Control ◽  
Significant Process ◽  
Technology Applications ◽  
And Performance ◽  
Physical And Chemical ◽  
Analytical Technology ◽  
And Chemical Properties

Crystallization is a significant process employed to produce a wide variety of materials in pharmaceutical and food area. The control of crystal dimension, crystallinity, and shape is very important because they will affect the subsequent filtration, drying and grinding performance as well as the physical and chemical properties of the material. This review summarizes the special features of crystallization technology and the preparation methods of nanocrystals, and discusses analytical technology which is used to control crystal quality and performance. The crystallization technology applications in pharmaceutics and foods are also outlined. These illustrated examples further help us to gain a better understanding of the crystallization technology for pharmaceutics and foods.

Construction of the Precision Solution Spraying System Based on Single-Axis Servo Control

2014 ◽  
Vol 940 ◽  
pp. 173-178
Author(s):  
Xiao Long Tang ◽  
Chun Ming Geng
Keyword(s):  
Chemical Properties ◽  
Servo Control ◽  
Industrial Processing ◽  
Precise Control ◽  
Mechanical Structure ◽  
Control Precision ◽  
Control Interface ◽  
Sealing Performance ◽  
Translation Stage ◽  
Physical And Chemical

In modern industrial processing of the materials, the solution spraying technology is widely used. Spraying a layer of special solution plays an important role to change their physical and chemical properties. Based on single-axis servo control, precision solution spraying system is able to spray a very thin and a uniform layer of solution on the surface of materials as required. The spraying system mechanical structure is mainly composed of these parts: housing, single-axis servo translation stage, push-pull syringe, multifunctional nozzle and other components. The servo translation stage is capable of providing precise control of speed and stroke by using a specialized controller and driver. The system is running stably and smoothly throughout the experiments after the completion of the entire system assembly and it can fully comply with the requirements of customers with excellent sealing performance, feature-rich and human-friendly control interface and compact mechanical structure.

scholarly journals Testing Engine Oil Specifications and Properties and its Effects on the Engines Maintenance and Performance

2020 ◽  
Vol 15 ◽  
Keyword(s):  
Chemical Properties ◽  
Mechanical Tests ◽  
Engine Oil ◽  
Strong Relation ◽  
Degree Of Stability ◽  
And Performance ◽  
The Cost ◽  
Motor Oils ◽  
Physical And Chemical ◽  
And Chemical Properties

This paper presents the results of practical mechanical tests of motor oils, their specifications and characteristics and the effect of their physical and chemical properties on the performance of the engine. The performance of the engine has a strong relation with the engine oil type and efficiency. The degree of stability of oils properties is very important because if oil or lubricants lose their properties, mechanical and chemical excessive corrosion of the motor metals may occur. Consequently, damage occurs to one or more parts of the engine, thereby the system is breaking down where the cost of downtime is too expensive. It has been found that a higher viscosity value is not the optimum as it increases temperature and energy consumption due to frictional losses. The values required for viscosity is the ideals that gives the stable results regardless temperature variations under any conditions of operation, at which the power losses are minimal and the fuel economy is optimal.

scholarly journals Expanding the molecular-ruler process through vapor deposition of hexadecanethiol

2017 ◽  
Vol 8 ◽  
pp. 2339-2344 ◽  
Author(s):  
Alexandra M Patron ◽  
Timothy S Hooker ◽  
Daniel F Santavicca ◽  
Corey P Causey ◽  
Thomas J Mullen
Keyword(s):  
Vapor Phase ◽  
Self Assembly ◽  
Chemical Properties ◽  
Solution Deposition ◽  
Precise Control ◽  
Vapor Phase Deposition ◽  
Great Utility ◽  
Complex Architectures ◽  
Molecular Ruler ◽  
Physical And Chemical

The development of methods to produce nanoscale features with tailored chemical functionalities is fundamental for applications such as nanoelectronics and sensor fabrication. The molecular-ruler process shows great utility for this purpose as it combines top-down lithography for the creation of complex architectures over large areas in conjunction with molecular self-assembly, which enables precise control over the physical and chemical properties of small local features. The molecular-ruler process, which most commonly uses mercaptoalkanoic acids and metal ions to generate metal-ligated multilayers, can be employed to produce registered nanogaps between metal features. Expansion of this methodology to include molecules with other chemical functionalities could greatly expand the overall versatility, and thus the utility, of this process. Herein, we explore the use of alkanethiol molecules as the terminating layer of metal-ligated multilayers. During this study, it was discovered that the solution deposition of alkanethiol molecules resulted in low overall surface coverage with features that varied in height. Because features with varied heights are not conducive to the production of uniform nanogaps via the molecular-ruler process, the vapor-phase deposition of alkanethiol molecules was explored. Unlike the solution-phase deposition, alkanethiol islands produced by vapor-phase deposition exhibited markedly higher surface coverages of uniform heights. To illustrate the applicability of this method, metal-ligated multilayers, both with and without an alkanethiol capping layer, were utilized to create nanogaps between Au features using the molecular-ruler process.

Study the Effects of Different Surfactants on Hydrophilicity of Polydimethylsiloxane (PDMS)

2012 ◽  
Author(s):  
Hojjat Madadi ◽  
Jasmina Casals-Terré
Keyword(s):  
Vapour Deposition ◽  
Low Cost ◽  
Chemical Vapour ◽  
Chemical Properties ◽  
Base Material ◽  
Hydrophobic Surface ◽  
Fabrication Procedure ◽  
Highly Hydrophobic ◽  
Physical And Chemical ◽  
And Chemical Properties

The outstanding characteristics of polydimethylsiloxane (PDMS) caused its extensive use as base material to manufacture microfluidic devices. PDMS has numerous advantages coming from instinct properties such as its low cost, simple fabrication procedure, and robust nature that make it a compatible material in many applications such as biological and biomedical engineering. In spite of favorable physical and chemical properties, hydrophobic surface of PDMS is sometimes debatable. Because of PDMS is highly hydrophobic, pumping aqueous solution through microchannels using only capillary forces might be difficult. Although many surface treatments methods have been proposed to modify and increase the hydrophilicity of PDMS [Oxygen plasma [1], UV-radiation [2], Silanization and Chemical vapour deposition [3],…], the use of surfactants is the most effective and easiest method to overcome the hydrophobicity compared to more complex protocols which require expensive facilities [4,5]. The hydrophilic behavior of surfactant-added PDMS and especially its biocompatibility has allowed many microfluidic bio-applications such as separation of biomolecules [6,7], blood cell separation [8] and cell-based assay [9,10]. This paper discusses about the efficiency of adding different surfactants on the wettability of PDMS.

Effects of dimethyl carbonate fuel additive on diesel engine performances

2005 ◽  
Vol 219 (7) ◽  
pp. 897-903 ◽  
Author(s):  
G D Zhang ◽  
H Liu ◽  
X X Xia ◽  
W G Zhang ◽  
J H Fang
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Diesel Engines ◽  
Dimethyl Carbonate ◽  
Chemical Properties ◽  
Fuel Additive ◽  
High Oxygen Content ◽  
Combustion Duration ◽  
And Performance ◽  
Physical And Chemical

The physical and chemical properties of some oxygenated compounds are discussed, including dimethoxymethane (methylal, or DMM), dimethyl carbonate (DMC), and ethyl acetate. In particular, DMC may be a promising additive for diesel fuel owing to its high oxygen content, no carbon-carbon atomic bonds, suitable boiling point, and solubility in diesel fuel. The aim of this research was to study the combustion characteristics and performance of diesel engines operating on diesel fuel mixed with DMC. The experimental results have shown that particulate matter (PM) emissions can be reduced using the DMC oxygenated compound. The combustion analysis indicated that the ignition delay of the engine fuelled with DMC-diesel blended fuel is longer, but combustion duration is much shorter, and the thermal efficiency is increased compared with that of a base diesel engine. Further, if injection is also delayed, NOx emissions can be reduced while PM emissions are still reduced significantly. The experimental study found that diesel engines fuelled with DMC additive had improved combustion and emission performances.

Preparation and Performance of Andalusite Bonded SiC Solar Heat-Absorbing Ceramics

2013 ◽  
Vol 320 ◽  
pp. 52-59
Author(s):  
Jian Feng Wu ◽  
Meng Liu ◽  
Xiao Hong Xu ◽  
Ya Xiang Zhang ◽  
Kun Li ◽  
...  
Keyword(s):  
Thermal Shock ◽  
Bending Strength ◽  
Thermal Power ◽  
Chemical Properties ◽  
Xrd Analysis ◽  
Expansion Rate ◽  
Testing Technology ◽  
Firing Shrinkage ◽  
And Performance ◽  
Physical And Chemical

Using andalusite, SiC, Su Zhou Kaolin and Guang Xi quartz as materials, andalusite bonded SiC heat absorbing ceramic was prepared by pressureless firing in the ceramic preparation process. The influence of gradient SiC on microstructure and properties of the samples were studied. Using the testing technology of XRD, SEM, and etc., physical and chemical properties, phase composition and microstructure were tested and analysised.The results indicate that andalusite bonded SiC heat absorbing ceramic, which prepared to have a low firing shrinkage rate, high refractoriness and a good microstructure. The best firing temperature of the best formula C4 is 1460°C, firing expansion rate is 0.98%, bending strength is 32.52MPa,porosity is 30.74%, bulk density is 2.05g·cm-3, refractoriness is 1650°C,growth rate of oxidation weight is 2.769mg·cm-2and have no crack after 30 times thermal shock. The bending strength has increased 11.15% after thermal shock. XRD analysis indicated that the main phase compositions are α-SiC, mullite and cristobalite.SEM studies show that there are many connected pores in the samples, the diameters of the pores are 10~20μm. Andalusite bonded SiC heat absorbing ceramic have a low firing expansion rate, high bending strength and good microstructure, which is suit for tower type solar thermal power generation.

scholarly journals Magnetic field–driven assembly and reconfiguration of multicomponent supraparticles

2020 ◽  
Vol 6 (19) ◽  
pp. eaba5337 ◽  
Author(s):  
A. Al Harraq ◽  
J. G. Lee ◽  
B. Bharti
Keyword(s):  
Magnetic Field ◽  
Three Dimensional ◽  
Chemical Properties ◽  
Building Blocks ◽  
Precise Control ◽  
Patchy Particles ◽  
Local Arrangement ◽  
Response To Change ◽  
Biological Complexes ◽  
Physical And Chemical

Suprastructures at the colloidal scale must be assembled with precise control over local interactions to accurately mimic biological complexes. The toughest design requirements include breaking the symmetry of assembly in a simple and reversible fashion to unlock functions and properties so far limited to living matter. We demonstrate a simple experimental technique to program magnetic field–induced interactions between metallodielectric patchy particles and isotropic, nonmagnetic “satellite” particles. By controlling the connectivity, composition, and distribution of building blocks, we show the assembly of three-dimensional, multicomponent supraparticles that can dynamically reconfigure in response to change in external field strength. The local arrangement of building blocks and their reconfigurability are governed by a balance of attraction and repulsion between oppositely polarized domains, which we illustrate theoretically and tune experimentally. Tunable, bulk assembly of colloidal matter with predefined symmetry provides a platform to design functional microstructured materials with preprogrammable physical and chemical properties.

Investigating the properties and performance of 3A molecular sieves as an adsorbent to prevent coke formation in olefin dehydration process

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zoya Moslempour ◽  
Sepehr Sadighi ◽  
Ali Dashti ◽  
Ali Ahmadpour
Keyword(s):  
Molecular Sieves ◽  
Molecular Sieve ◽  
Coke Formation ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Na Ions ◽  
Temperature Programmed ◽  
And Performance ◽  
Physical And Chemical

Abstract To study the affinity of 3A aluminosilicate adsorbents to prevent oligomerization of olefin molecules and forming green oil, physical and chemical properties of 3A molecular sieves are measured by using characterization techniques such as temperature-programmed desorption (TPD), nitrogen (N2) and water adsorptions, X-ray diffraction (XRD), X-ray fluorescence (XRF), crushing strength, and carbon dioxide (CO2) adsorption. Moreover, coke formation affinities of the understudy adsorbents are evaluated in a bench-scale system using 1-butene and 1,3-butadiene at temperatures of 220 and 260 °C, and outcomes are validated against the actual data gathered from an industrial scale olefin dehydration plant. Results confirm that the type of binder and the amount of ion exchange affect the performance of a 3A molecular sieve nominated for dehydrating olefinic streams. The binder with the least amount of acidity is preferred, and at least 35% of Na ions of the 4A zeolite should be exchanged with K ions to make it applicable for synthesizing an appropriate 3A molecular sieve. Furthermore, to control the oligomerization and inhibit green oil formation, the CO2 adsorption and acidity of Trisiv shape molecular sieves with the sizes of 1/4 inch should be less than 0.5 wt % and 1.7 mmol NH3/g, respectively. For extrudate shape with the sizes of 1/16 inch CO2 adsorption and acidity should be less than 0.2 wt % and 2.2 mmol NH3/g, respectively.

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