Physical and performance characteristics of nonwoven aviation wipers composed of various staple fibers including raw cotton

2018 ◽  
Vol 49 (9) ◽  
pp. 1198-1217
Author(s):  
Rebecca J Hron ◽  
Doug J Hinchliffe ◽  
Michael S Cintrón ◽  
Terri Von Hoven ◽  
Crista A Madison ◽  
...  

Several nonwoven materials were evaluated as candidates for wipe fabrics intended for sensitive applications, namely aviation maintenance. Wipes designed for this purpose must conform to specific guidelines delineated by the appropriate governing bodies. Fabric selections included both synthetic and natural staple fibers such as polyester, Lyocell and raw cotton varieties. A thorough evaluation of extractable material in an array of solvents revealed that cotton-based nonwovens as well as Lyocell have some of the lowest percentages of leachable solids. The resistance of these fabrics to abrasion and the damage incurred by them was also studied. Environmental scanning electron microscopy taken before and after the linting procedure showed that the greige cotton sample demonstrated some of the least damage. Fourier-transform infrared spectroscopy examinations of hexane extracts confirmed the absence of any silicone grease contamination on the wipes materials. Standardized tensile testing indicated that the cotton samples, especially mechanically cleaned greige cotton, have robust tensile properties that are important characteristics for wiping materials. These results indicate that cotton nonwovens, particularly greige cotton, are promising candidates for the development of future aviation and other wipes materials.

2015 ◽  
Vol 10 (1) ◽  
pp. 155892501501000 ◽  
Author(s):  
Fengyan Li ◽  
Hongjun Fu

Lotus fibers are pulled from different period of lotus root. Alkaline was used as degumming agent to remove non-cellulose impurities of lotus fibers. Environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD) and FTIR were used to characterize surface morphology and microscopic structure of lotus fibers before and after degumming. The effect of alkaline degumming on tensile properties of lotus fibers is investigated. The results show that impurities remove, hydrogen bond rupture, and crystallinity of partly armorphous chain occur during alkaline degumming. All of these changes play roles in influencing fiber tensile breaking force and elongation at break.


Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 25 ◽  
Author(s):  
Maria Gandolfi ◽  
Paola Taddei ◽  
Anna Pondrelli ◽  
Fausto Zamparini ◽  
Carlo Prati ◽  
...  

The aim of the study was to investigate the effects of several decalcifying agents used as irrigant solutions in endodontic treatment on collagen and mineral components of dentin. Coronal dentin discs from five caries-free human third molars with a smear layer were treated for one minute with a chelating solution (1% Ethylenediaminetetraacetic acid (EDTA), 10% EDTA, 17% EDTA, 10% citric acid). Mineralization degree (Ca/N and P/N atomic ratios, IR Iapatite/Iamide II and I1410(carbonate)/I554(phosphate) spectroscopic ratios) and possible collagen rearrangements (collagen infrared (IR) amide II e III shifts) were evaluated by environmental scanning electron microscopy (ESEM)/energy dispersive X-ray spectroscopy (EDX) and IR spectroscopy before and after treatment (T0) and after ageing (T24h and T2m) in simulated body fluid (SBF). At T0, analysis showed that the highest demineralizing effect was achieved using a 10% citric acid solution and 10% EDTA, while the smallest effect was observed when using 17% EDTA. No significant collagen modifications were detected upon treatment with 1% EDTA, while subtle changes were observed after the other treatments. At T24h or T2m, analyses showed the highest remineralization values for 1% EDTA and the lowest for 10% citric acid, mainly at T2m. The samples treated with 17% EDTA showed slight collagen rearrangements upon remineralization. In conclusion, the highest demineralizing effect was observed for 10% EDTA and 10% citric acid. Collagen rearrangement was found for all the treatments except for 1% EDTA. The highest remineralization capability in SBF values was recorded for 1% EDTA and the lowest for 10% citric acid. A slight collagen rearrangement upon remineralization was still present in 17% EDTA-treated samples. Clinical use as a chelating agent in the endodontic therapy of citric acid and concentrated EDTA solutions should be reconsidered.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Lijuan Han ◽  
Qingyuan Chen ◽  
Hong Chen ◽  
Shang Yu ◽  
Lin Xiao ◽  
...  

The α-zirconium phosphate (α-ZrP) and hydrophobically modified α-zirconium phosphate (α-ZrP-I) were prepared. The grafting of octadecyl isocyanate was confirmed by Fourier transform infrared (FTIR) spectra, X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The dispersion of α-ZrP-I was studied by environmental scanning electron microscopy (SEM). The wettability of α-ZrP-I was determined by Kruss DSA30. Then, the effects of decompression and augmented injection of α-ZrP-I have been studied. The results of water flooding experiments show that the appropriate concentration of α-ZrP-I has an effect on the decrease of the water injection pressure.


2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Tomás Agustín Rearte ◽  
Patricia Beatriz Bozzano ◽  
Maria Luisa Andrade ◽  
Alicia Fabrizio de Iorio

Biosorption and desorption of chromium and lead on shoots biomass of Schoenoplectus californicus were investigated by performing batch sorption tests in different conditions of pH, biosorbent dose, and initial concentration in simple and binary solutions. Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm models were employed to describe sorption equilibrium. Filters and biomass were characterized before and after treatments by environmental scanning electron microscopy and X-ray energy-dispersive spectrometry. The optimal conditions for biosorption were found to be pH 5 for both metals. The contact time to reach pseudoequilibrium changed as a function of pH and the metal studied. The highest optimisation of biosorbent dose was 5 g L−1 at pH 7 and 15 g L−1 at pH 5 for both metals. The most effective extracting agents for lead and chromium proved to be HNO3 and NaOH, respectively. The recovery of lead was greater than of chromium because the Cr(III) sorption mechanisms involve a stronger binding energy than the mechanisms for Pb(II), such as in intern sphere complexes. Both metals accounted for a high % removal (>90%) under the best sorption conditions. The use of Schoenoplectus californicus proved to be an efficient and economical alternative for the treatment of effluents contaminated with lead and chromium.


2011 ◽  
Vol 418-420 ◽  
pp. 610-616 ◽  
Author(s):  
Cui Xia Li ◽  
Guang Hua Wen ◽  
Jian Jun Yang ◽  
Jian Guo Li ◽  
Yang Fan Zhou

Through laboratory experiments, a green cross-linked movable gel has been developed, which has been used for reservoir profile modification. The main agent of gel is hydrophobic associating polymer, concentration is 3000mg/L; the cross-linking agent is Aluminum citrate from complex of Aluminum ion and citric acid root ion. The best molar ratio of aluminum ions and citrate ions is 1.5:1 in complex reaction, the amount is 140mg/L; the retarder is tartaric acid sodium, the amount is 150mg/L; The stabilizer is thiourea, the amount is 800mg/L; The strength of the green cross-linked movable gel is 3.12×104mPa.s, gelling time 36h, Stable time 160d; It is suitable for low-temperature reservoir profile modification, and salt resistance is good. Laboratory experiments show that the green cross-linked movable gel have strong plugging capacity and improving profile ability. The green cross-linked movable gel has strong three dimensional network structure, which be observed through the environmental scanning electron microscopy.


Author(s):  
Howard S. Kaufman ◽  
Keith D. Lillemoe ◽  
John T. Mastovich ◽  
Henry A. Pitt

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.


Author(s):  
Klaus-Ruediger Peters

Environmental SEM operate at specimen chamber pressures of ∼20 torr (2.7 kPa) allowing stabilization of liquid water at room temperature, working on rugged insulators, and generation of an environmental secondary electron (ESE) signal. All signals available in conventional high vacuum instruments are also utilized in the environmental SEM, including BSE, SE, absorbed current, CL, and X-ray. In addition, the ESEM allows utilization of the flux of charge carriers as information, providing exciting new signal modes not available to BSE imaging or to conventional high vacuum SEM.In the ESEM, at low vacuum, SE electrons are collected with a “gaseous detector”. This detector collects low energy electrons (and ions) with biased wires or plates similar to those used in early high vacuum SEM for SE detection. The detector electrode can be integrated into the first PLA or positioned at any other place resulting in a versatile system that provides a variety of surface information.


2021 ◽  
Vol 99 (3) ◽  
Author(s):  
Y Zhu ◽  
L J Johnston ◽  
M H Reese ◽  
E S Buchanan ◽  
J E Tallaksen ◽  
...  

Abstract This study was conducted to evaluate whether cooled floor pads combined with chilled drinking water could alleviate negative impacts of heat stress on lactating sows. Thirty sows (Landrace × Yorkshire, Parity = 1 to 6) were housed in individual farrowing stalls in two rooms with temperatures being controlled at 29.4°C (0700–1900 hours) and 23.9°C (1900–0700 hours). Sows in one room (Cool), but not in the other room (Control) were provided cooled floor pads (21–22°C) and chilled drinking water (13–15°C). Behavior of sows (15 sows/treatment) was video recorded during farrowing, and days 1, 3, 7, 14, and 21 after farrowing. Videos were viewed continuously to register the birth time of each piglet, from which total farrowing duration and birth intervals were calculated. The number of drinking bouts and the duration of each drinking bout were registered for each sow through viewing videos continuously for 2 h (1530–1730 hours) each video-recording day. Postures (lying laterally, lying ventrally, sitting, and standing) were recorded by scanning video recordings at 5-min intervals for 24 h each video-recording day, and time budget for each posture was calculated. Rectal temperature and respiration rate were measured for all sows the day before and after farrowing, and then once weekly. Sow and litter performance was recorded. Data were analyzed using the Glimmix procedure of SAS. The cooling treatment did not affect sow behavior or litter performance. Sows in the Cool room had lower rectal temperature (P = 0.03) and lower respiration rate (P < 0.001), consumed more feed (P = 0.03), tended to have reduced weight loss (P = 0.07), and backfat loss (P = 0.07) during lactation than sows in the Control room. As lactation progressed, sows increased drinking frequency (P < 0.001) and time spent lying ventrally (P < 0.0001), standing (P < 0.001), and sitting (P < 0.0001), and decreased time spent lying laterally (P < 0.0001) in both Cool and Control rooms. While cooled floor pads combined with chilled drinking water did not affect sow behavior, they did alleviate heat stress partially, as indicated by decreased rectal temperature, respiration rate, weight, and backfat loss, and increased feed intake in lactating sows.


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