scholarly journals Investigation of frictional impact on polyester yarn during knitting

2021 ◽  
Vol 72 (06) ◽  
pp. 595-600
Author(s):  
ALI AFZAL ◽  
ABDUL WAQAR RAJPUT ◽  
HAFSA JAMSHAID ◽  
SAJID HUSSAIN ◽  
SYEDA SIDRA BATOOL ◽  
...  

The usage of polyester (PET) in fabrication is increasing day by day due to its properties, ease of physical and chemical modification. The aim of this work is to understand the effect of temperature on Polyester (PET) during knitting. For checking the rise of temperature Infrared (IR) camera is used. Microscopic images are used for studying the effect of temperature on fibre/yarn structure. Morphological analysis is also done by X-ray diffraction (XRD) which shows disturbance of polymeric chains, causing change in crystal size due to elevated temperature. The beads formation and filament breakage are clearly seen in images. Due to this knitting fault, shade variation after dyeing occurred. It is concluded that structural morphology of polyester yarn changes due to friction of yarn with knitting machine parts. Fabric appearance and fabric quality also disturbed which leads to rejections and high losses.

2014 ◽  
Vol 900 ◽  
pp. 172-176 ◽  
Author(s):  
Ji Mei Niu ◽  
Zhi Gang Zheng

The Fe3O4 magnetic nanoparticles obtained by the aqueous coprecipitation method are characterized systematically using scanning electron microscope, X-ray diffraction and vibrating sample magnetometer. These magnetic nanoparticles are spheric, dispersive, and have average grain size of 50 nm. The size and magnetic properties of Fe3O4 nanoparticles can be tuned by the reaction temperature. All samples exhibit high saturation magnetization (Ms=53.4 emu·g-1) and superparamagnetic behavior with a block temperature (TB) of 215K. These properties make such Fe3O4 magnetic nanoparticles worthy candidates for the magnetic carriers of targeted-drug or gene therapy in future.


2019 ◽  
Vol 17 (1) ◽  
pp. 1459-1465
Author(s):  
Xuedong Feng ◽  
Jing Yi ◽  
Peng Luo

AbstractWith the purpose of studying the influence of NO/O2 on the NOx storage activity, a Pt-Ba-Ce/γ-Al2O3 catalyst was synthesized by an acid-aided sol-gel method. The physical and chemical properties of the catalyst were characterized by X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) methods. The results showed that the composition of the catalyst was well-crystallized and the crystalline size of CeO2 (111) was about 5.7 nm. The mechanism of NO and NO2 storage and NOx temperature programmed desorption (NO-TPD) experiments were investigated to evaluate the NOx storage capacity of the catalyst. Pt-Ba-Ce/γ-Al2O3 catalyst presented the supreme NOx storage performance at 350℃, and the maximum value reached to 668.8 μmol / gcat. Compared with O2-free condition, NO oxidation to NO2 by O2 had a beneficial effect on the storage performance of NOx. NO-TPD test results showed that the NOx species stored on the catalyst surface still kept relatively stable even below 350℃.


1987 ◽  
Vol 113 ◽  
Author(s):  
Scott Schlorholtz ◽  
Ken Bergeson ◽  
Turgut Demirel

ABSTRACTThe physical and chemical properties of fly ash produced at Ottumwa Generating Station have been monitored since April, 1985. The fly ash is produced from burning a low sulfur, sub-bituminous coal obtained from the Powder River Basin near Gillette, Wyoming. One-hundred and sixty samples of fly ash were obtained during the two year period. All of the samples were subjected to physical testing as specified by ASTM C 311. About one-hundred of the samples were also subjected to a series of tests designed to monitor the self-cementing properties of the fly ash. Many of the fly ash samples were subjected to x-ray diffraction and fluorescence analysis to define the mineralogical and chemical composition of the bulk fly ash as a function of sampling date. Hydration products in selected hardened fly ash pastes, were studied by x-ray diffraction and scanning electron microscopy. The studies indicated that power plant operating conditions influenced the compressive strength of the fly ash paste specimens. Mineralogical and morphological studies of the fly ash pastes indicated that stratlingite formation occurred in the highstrength specimens, while ettringite was the major hydration product evident in the low-strength specimens.


2003 ◽  
Vol 807 ◽  
Author(s):  
T. Advocat ◽  
F. Jorion ◽  
T. Marcillat ◽  
G. Leturcq ◽  
X. Deschanels ◽  
...  

ABSTRACTZirconolite is a potential inorganic matrix that is currently investigated in France, in the framework of the 1991 radioactive waste management law, with a view to provide durable containment of the trivalent and tetravalent minor actinides like neptunium, curium, americium and small quantities of unrecyclable plutonium separated from other nuclear waste. To confirm the actinide loading capacity of the zirconolite calcium site and to study the physical and chemical stability of this type of ceramic when subjected to alpha self-irradiation, zirconolite ceramic pellets were fabricated with 10 wt% plutonium oxide (isotope 239 or 238). The 55 pellets are dense (> 93.3% of the theoretical density on average) and free of cracks. They are characterized by a grain size of between 10 and 20 micrometers. X-ray diffraction analyses confirmed the presence of the zirconolite 2M crystalline structure.


2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Yan Li ◽  
Chuan-Sheng Liu ◽  
Yun-Ling Zou

AbstractZnO nano-tubes (ZNTs) have been successfully synthesized via a simple hydrothermal-etching method, and characterized by X-ray diffraction, field emission scanning electron microscopy and room temperature photoluminescence measurement. The as-synthesized ZNTs have a diameter of 500 nm, wall thickness of 20–30 nm, and length of 5 µm. Intensity of the plane (0002) diffraction peak, compared with that of plane (10$$ \bar 1 $$0) of ZNTs, is obviously lower than that of ZnO nano-rods. This phenomenon can be caused by the smaller cross section of plane (0002) of the nano-tubes compared with that of other morphologies. On basis of the morphological analysis, the formation process of nano-tubes can be proposed in two stages: hydrothermal growth and reaction etching process.


2012 ◽  
Vol 31 (1) ◽  
pp. 79
Author(s):  
Khalil Faghihi ◽  
Masoumeh Soleimani ◽  
Shabnam Nezami ◽  
Meisam Shabanian

Two new samples of poly(amide-imide)-montmorillonite reinforced nanocomposites containing N-trimellitylimido-L-valine moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 5 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N-trimellitylimido-L-valine (3) with 4,4′-diaminodiphenyl ether 4 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PA-nanocomposite films (5a) and (5b) with 10 and 20 % silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposite films were investigated by using Uv-vis spectroscopy,  thermogravimetric analysis (TGA) and water uptake measurements.


Author(s):  
Alaa Mohamed Elsafi ◽  
Vinotha Krishnasamy ◽  
Karthik Kannan ◽  
John-John Cabibihan ◽  
Abdulaziz Khalid AlAli ◽  
...  

High levels of glucose or acetone in breath confirms diabetes disease. One of the analytical devices that detect changes in breath is the electrochemical sensor having high selectivity, easy to use and being able to meet diabetic patient’s needs. In this study, sensors were made by fabricating metal oxide coated glassy carbon electrodes and using nafion as a proton conductor. Characterization methods such as X-ray diffraction, FTIR and morphological analysis have been performed for metal oxides to characterize their atomic arrangement and composition. In addition, electrochemical studies were done using Gamry instrument and curves plotted as current in amperes versus voltage to test the coated electrodes conductivity. High selectivity sensors provide promising applications in any field.


Author(s):  
Shuo Xu ◽  
Shi-Jie Wang ◽  
Li Xiao-Hong ◽  
Hong-Ling Cui

Defect and doping are effective methods to modulate the physical and chemical properties of materials. In this report, we investigated the structural stability, electronic properties and quantum capacitance (Cdiff) of Zr2CO2 by changing the dopants of Si, Ge, Sn, N, B, S and F in the substitutional site. The doping of F, N, and S atoms makes the system undergo the semiconductor-to-conductor transition, while the doping of Si, Ge, and Sn maintains the semiconductor characteristics. The Cdiff of the doped systems are further explored. The B-doped system can be used as cathode materials, while the systems doped by S, F, N, Sn atoms are promising anode materials of asymmetric supercapacitors, especially for the S-doped system. The improved Cdiff mainly originates from Fermi-level shifts and Fermi-Dirac distribution by the introduction of the dopant. The effect of temperature on Cdiff is further explored. The result indicates that the maximum Cdiff of the studied systems gradually decreases with the increasing temperature. Our investigation can provide useful theoretical basis for designing and developing the ideal electrode materials for supercapacitors.


There are numerous previous studies working on biosynthesis, properties and applications of bacterial cellulose (BC) membrane from Acetobacter xylinum bacteria strain. However, there is less research examining the effect of initial pH level on BC membrane properties. Here, BC membranes were produced at different pH level (concentration of acetic acid) of coconut water-based culture medium which are 3.5, 4.0, 4.5, 5.0 and 5.5 for 7 days, statically. The effect of initial pH level during BC production on morphology, physical and characteristics were investigated. The Acetobacter xylinum membrane were studied its crystallinity using X-ray diffraction, FTIR analysis for chemical structure and FESEM for morphological analysis. In addition, the different of initial pH level does affect the membrane yield and breathability properties using an Upright Cup Method of water vapour permeability testing. Although certain suitable amount of acid had reduced the production yield, a breathable BC membrane was produced.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
H. F. Lopez ◽  
H. Mendoza

The effect of temperature on nano-CeO2 particle coarsening is investigated. The nanoceria powders were synthesized using the microemulsion method and then exposed to temperatures in the range of 373–1273 K. It was found that the nanoparticles exhibited a strong tendency to form agglomerates and through the application of ultrasound these agglomerates could be broken into smaller sizes. In addition average nanoparticle sizes were determined by powder X-ray diffraction (XRD). The outcome of this work indicates that the initial nano-CeO2 powders are amorphous in nature. Annealing promotes CeO2 crystallization and a slight shift in the (111) XRD intensity peaks corresponding to CeO2. Moreover, at temperatures below 773 K, grain growth in nano-CeO2 particles is rather slow. Apparently, mass transport through diffusional processes is not likely to occur as indicated by an estimated activation energy of 20 kJ/mol. At temperatures above 873 K, the measured activation energy shifted to 105 kJ/mol suggesting a possible transition to Ostwald-Ripening type mass transport mechanisms.


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