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1
James, Veronica. "A Review of Low Angle Fibre Diffraction in the Diagnosis of Disease." British Journal of Medicine and Medical Research 3, no. 2 (2013): 383–97. http://dx.doi.org/10.9734/bjmmr/2013/2432.
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Holmes, K. C., and G. Rosenbaum. "How X-ray Diffraction with Synchrotron Radiation Got Started." Journal of Synchrotron Radiation 5, no. 3 (1998): 147–53. http://dx.doi.org/10.1107/s0909049597018578.
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The need to record low-angle-scattering X-ray fibre diagrams from muscle with millisecond time resolution drove the use of synchrotron radiation as an X-ray light source. The first smudgy diffraction patterns were obtained from a slice of insect flight muscle. Out of this grew the EMBL Outstation at DESY.
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Starink, Marco J., Shun Cai Wang, Nong Gao, H. Singh Ubhi, Cheng Xu, and Terence G. Langdon. "An EBSD Study of Texture and Grain Boundary Evolution in a Strongly Textured Aluminium Alloy during ECA Pressing." Materials Science Forum 503-504 (January 2006): 937–42. http://dx.doi.org/10.4028/www.scientific.net/msf.503-504.937.
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The texture and grain boundary evolution during equal channel angular pressing (ECAP) of a spray-cast Al-7034 (Al-Zn-Mg-Cu) alloy containing intermetallic particles with a range of sizes was studied through electron backscatter diffraction (EBSD). Up to 8 passes of ECAP using route Bc were employed. The initial ECAP pass leads to the development of low angle grain boundaries and subsequent passes lead to a relatively rapid increase in the fraction of high angle grain boundaries. Before ECAP, the material possessed a strong <111> and <100> fibre texture. On ECAP, the <111> fibre texture component is mostly retained but the <100> fibre develops to a Cube texture after the first ECAP pass. Goss textures form from about 4 passes of ECAP.
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James, Veronica. "The Molecular Architecture for the Intermediate Filaments of Hardα-Keratin Based on the Superlattice Data Obtained from a Study of Mammals Using Synchrotron Fibre Diffraction". Biochemistry Research International 2011 (2011): 1–10. http://dx.doi.org/10.1155/2011/198325.
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High- and low-angle X-ray diffraction studies of hardα-keratin have been studied, and various models have been proposed over the last 70 years. Most of these studies have been confined to one or two forms of alpha keratin. This high- and low-angle synchrotron fibre diffraction study extends the study to cover all available data for all known forms of hardα-keratin including hairs, fingernails, hooves, horn, and quills from mammals, marsupials, and a monotreme, and it confirms that the model proposed is universally acceptable for all mammals. A complete Bragg analysis of the meridional diffraction patterns, including multiple-time exposures to verify any weak reflections, verified the existence of a superlattice consisting of two infinite lattices and three finite lattices. An analysis of the equatorial patterns establishes the radii of the oligomeric levels of dimers, tetramers, and intermediate filaments (IFs) together with the centre to centre distance for the IFs, thus confirming the proposed helices within helices molecular architecture for hardα-keratin. The results verify that the structure proposed by Feughelman and James meets the criteria for a validα-keratin structure.
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Sahoo, M., B. Mallick, S. Rout, and G. N. Dash. "Structural and Mechanical Strength of Proton Radiation Processed Polyethylene Terephthalate." Journal of Scientific Research 12, no. 1 (2020): 83–91. http://dx.doi.org/10.3329/jsr.v12i1.43168.
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The change in structural and mechanical behavior of polyethylene terephthalate (PET) due to 2.4 MeV proton has been studied. Radiation processing of PET polymer is carried out using different low doses such as 0.2, 2.0, and 20 kGy. The Physics of microstrain and radiation-induced mesophase formation are analysed. X-ray investigation indicates that proton-induced structural modification takes place in the material. Apart from usual diffraction peaks, a low intensity broad peak is observed at small angle of about 2q =10º, when the fibre axis is mounted parallel to the X-ray direction. Such peak is absent in the diffraction spectrum when the fibre axis is mounted perpendicular to the beam direction. The appearance of the extra peak in a particular orientation confirms that, the phase is 2-dimensionally oriented (mesophase). The Young’s modulus (Y) of this irradiated PET sample is found to be more than that of the virgin sample with the highest value recorded for a dose of 2.0 kGy. The decrease in Y for higher dose (20 kGy) may be due to enhanced ion-induced microstrain in the sample, causing degradation in mechanical strength.
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AL-Khayat, Hind. "Modelling Oriented Macromolecular Assemblies from Low-Angle X-ray Fibre Diffraction Data with the Program MOVIE: Insect Flight Muscle as Example." Fibre Diffraction Review 12, no. 12 (2004): 50. http://dx.doi.org/10.1382/s20041250.
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Díaz-Fuentes, M., E. Novillo, Amaia Iza-Mendia, and Isabel Gutiérrez. "Cold Rolled Microstructure and Its Evolution during Recovery and First Recrystallisation Stages in Low Carbon Steels." Materials Science Forum 467-470 (October 2004): 241–46. http://dx.doi.org/10.4028/www.scientific.net/msf.467-470.241.
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During annealing of cold rolled steel sheets, the evolution of the texture, to produce the characteristic texture of a recrystallised material, depends on a series of factors, including the starting deformation texture, composition and processing conditions. In the present work, electron backscattered diffraction (EBSD) techniques have been used to investigate the deformation substructures being developed by cold rolling into grains belonging to different texture components. The strain localisation, the deformation banding, the spread in orientation into grains with different orientations are some of the aspects that have been considered. Annealing cycles at different temperatures have also been carried out in order to promote recovery and initial stages of recrystallisation . The obtained substructures have been compared to the as-cold rolled ones. It has been observed that recovery induces the dislocation structures to arrange into subgrains. Associated to the ND fibre, a network of relatively high angle boundaries develop within the subgrain structure. The recrystallisation nuclei have been observed to evolve from such a network.
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Washusen, R., P. Ades, R. Evans, J. Ilic, and P. Vinden. "Relationships between Density, Shrinkage, Extractives Content and Microfibril Angle in Tension Wood from Three Provenances of 10-Year-Old Eucalyptus globulus Labill." Holzforschung 55, no. 2 (2001): 176–82. http://dx.doi.org/10.1515/hf.2001.029.
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Summary Density and microfibril angle (MFA) of tension wood and normal wood were assessed in the sapwood and heartwood, from three provenanaces of 10-year-old Eucalyptus globulus Labill. Density was measured using a modified saturation method that also enabled the calculation of the extractives lost during saturation. Microdensity and MFA were determined by SilviScan 2, a rapid X-ray densitometry and X-ray diffraction system developed at CSIRO. Significant differences were found in density and extractives between provenances and also density between the sapwood and adjacent heartwood from each provenance. This result may explain some of the drying differences between provenances found in an earlier study (Washusen and Ilic 2000). Sapwood samples with high percentages of tension wood fibres had high density and a significant positive correlation was found between microdensity and tension wood fibre percentage. MFA was found to be very low in normal wood in the sapwood, where most tension wood was found, so tension wood could not be identified by MFA. The positive association between tension wood and wood density suggests that caution should be taken when selecting trees for high wood density in tree improvement programs.
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Janicki, Jaroslaw. "Time-resolved small-angle X-ray scattering and wide-angle X-ray diffraction studies on the nanostructure of melt-processable molecular composites." Journal of Applied Crystallography 36, no. 4 (2003): 986–90. http://dx.doi.org/10.1107/s0021889803008495.
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Novel melt-processable molecular composites were obtained from isotactic polypropylene (iPP) and liquid-crystalline oligoester (LCO). The nanostructure and thermal behaviour of molecular composites were examined by real-time synchrotron small-angle X-ray scattering and wide-angle X-ray diffraction methods, and differential scanning calorimetry. The synthesized oligoester, with low melting temperature (391 K), exhibits the ability to form a thermotropic mesophase. It was shown that strong rigid rod-like macromolecules of LCO are dispersed at the molecular scale in iPP matrix and act as reinforcing fibres.
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Squire, John M., Carlo Knupp, Hind A. AL-Khayat, and J. Harford. "Millisecond Time-Resolved Low-angle X-ray Fibre Diffraction: A Powerful, High-Sensitivity Technique for Modelling Real-Time Movements in Biological Macromolecular Assemblies." Fibre Diffraction Review 11, no. 11 (2003): 28. http://dx.doi.org/10.1382/s20031128.
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Torbet, J. "Fibrin assembly after fibrinopeptide A release in model systems and human plasma studied with magnetic birefringence." Biochemical Journal 244, no. 3 (1987): 633–37. http://dx.doi.org/10.1042/bj2440633.
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Magnetically induced birefringence was used to monitor fibrin polymerization after the release of the small negatively charged A fibrinopeptides from human fibrinogen by the action of the snake-venom-derived enzymes reptilase and ancrod. A range of conditions was investigated. Fibrin polymerization in solutions of purified fibrinogen shows a distinct break near the gelation point. On addition of Ca2+ or albumin the lag period is shortened, fibre thickness is increased and the break in assembly almost vanishes, probably because both of these additives promote lateral aggregation. There are minor differences in the kinetics, depending on the venom enzyme used. The kinetics of fibrin assembly in model systems containing either Ca2+ or albumin and in human plasma with a largely dormant coagulation cascade are very similar. Therefore in the latter condition there is no significant alteration in the assembly process due to interaction between fibrin or the venom enzymes and any of the plasma proteins. When the cascade is activated, the polymerization progress curves have a character that resembles a combination of the reactions observed when the venom enzymes and endogenously generated thrombin separately induce coagulation, except for a region near gelation where, paradoxically, polymerization appears to be slower on activation. The low-angle neutron-diffraction patterns from oriented gels made with thrombin or reptilase are identical. Therefore at low resolution the packing of the monomers within fibres is the same when fibrinopeptide A only or both fibrinopeptides A and B are removed.
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Wang, Zhi Fen, Rong Dong Han, Shun Bing Zhou, Zhong Hai Yao, and Li Xin Wu. "Effect of Annealing Time on the Microstructure and Texture of Interstitial Free Steel." Advanced Materials Research 535-537 (June 2012): 593–96. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.593.
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Effect of annealing time on the microstructure and texture of IF steel sheets was investigated. Average grain size, grain boundary character and recrystallization texture were measured by X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) in order to clarify the effect of annealing time on microstructure of recrystallization process. The average grain size increased with increasing annealing time. With rising annealing time, the number of low angle boundary (0～15o) decreased due to the mergence of grain with sub-boundary. The //ND (-fiber) pole intensity had a highest value annealed at 60s. The annealing time played an important role in recrystallization process which affected the mechanical properties and microstructure of IF steels.
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Jin, Xiangyu, Lu Lu, Haibo Wu, Qinfei Ke, and Hong Wang. "Duck Feather/Nonwoven Composite Fabrics for Removing Metals Present in Textile Dyeing Effluents." Journal of Engineered Fibers and Fabrics 8, no. 3 (2013): 155892501300800. http://dx.doi.org/10.1177/155892501300800311.
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In this paper, duck feather fiber was treated by alkaline solution first, then its Cu2+ sorption capacity was tested, and the sorption mechanism was studied by utilizing infrared spectrum (FTIR) and wide-angle X-ray diffraction (XRD). Moreover, desorption properties of the treated duck feather fiber were investigated in order to exploit it as a recycled industrial effluent treatment material. Finally, the duck feather fiber was air-laid and thermal-bonded into a composite nonwoven fabric by adding bicomponent low melt PE/PP binder fiber. It was found that the alkaline treated duck feather/bicomponent PE/PP nonwoven fabrics exhibit good mechanical properties and Cu2+ and Cr6+ sorption capacity is a promising material for textile dyeing effluent treatment.
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Wang, Hong, Qi Ren, Xiang Yu Jin, and Hai Bo Wu. "Duck Feather Nonwoven Fabrics for Textile Dying Effluent." Advanced Materials Research 518-523 (May 2012): 1885–92. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.1885.
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In this paper, duck feather fiber was treated by alkaline solution first, then its Cu2+ sorption capacity was tested and the sorption mechanism was studied by utilizing infrared spectrum (FTIR) and wide-angle X-ray diffraction (XRD). Moreover, desorption properties of the treated duck feather fiber were investigated in order to exploit it as a recycled industrial effluent treatment material. At last, duck feather fiber was air-laid and thermal-bonded into a kind of composite nonwoven fabric by adding bicomponent low melt PE/PP fiber as binder fiber. It is found that duck feather/bicomponent PE/PP fiber composite nonwoven fabrics show good mechanical properties and Cu2+ and Cr6+ sorption capacity. It is a promising material for textile dying effluent treatment.
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Kim, Youngin, Hyeonho Yoon, Jong-Bum You, Minchul Kim, and Hyo-Hoon Park. "Wide-Angle Beam-Steering Using an Optical Phased Array with Non-Uniform-Width Waveguide Radiators." Photonics 7, no. 3 (2020): 56. http://dx.doi.org/10.3390/photonics7030056.
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We demonstrate wide-angle beam-steering using an optical phased array (OPA) with waveguide radiators designed with non-uniform widths to reduce the crosstalk between waveguides. The OPA consists of a silicon based 1 × 16 array of electro-optic phase shifters and end-fire radiators. The 16 radiators were configured with four different widths and a half-wavelength spacing, which can remove the higher-order diffraction patterns in free space. The waveguides showed a low crosstalk of −10.2 dB at a wavelength of 1540 nm. With phase control, the OPA achieved wide beam-steering of over ±80° with a side-lobe suppression of 7.4 dB.
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Tokuda, Tomoki, Ryo Tsuruda, Takuya Hara, et al. "Structure and Properties of Poly(ethylene terephthalate) Fiber Webs Prepared via Laser-Electrospinning and Subsequent Annealing Processes." Materials 13, no. 24 (2020): 5783. http://dx.doi.org/10.3390/ma13245783.
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Melt-electrospinning is an eco-friendly method for producing ultra-fine fibers without using any solvent. We prepared webs of poly(ethylene terephthalate) (PET) through melt-electrospinning using CO2 laser irradiation for heating. The PET webs comprised ultra-fine fibers of uniform diameter (average fiber diameter = 1.66 μm, coefficient of variation = 19%). The co-existence of fibers with high and low molecular orientation was confirmed through birefringence measurements. Although the level of high orientation corresponded to that of commercial highly oriented yarn, crystalline diffraction was not observed in the wide-angle X-ray diffraction (WAXD) analysis of the webs. The crystallinity of the webs was estimated using differential scanning calorimetry (DSC). The fibers with higher birefringence did not exhibit any cold crystallization peak. After annealing the web at 116 °C for 5 min, a further increase in the birefringence of the fibers with higher orientation was observed. The WAXD results revealed that the annealed webs showed crystalline diffraction peaks with the orientation of the c-axis along the fiber axis. In summary, the formation of fibers with a unique non-crystalline structure with extremely high orientation was confirmed.
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Hopkins, Jesse, Maxwell Watkins, and Thomas Irving. "New SAXS capabilities at BioCAT after the APS upgrade." Structural Dynamics 12, no. 2_Supplement (2025): A227. https://doi.org/10.1063/4.0000533.
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The BioCAT beamline (sector 18) at the Advanced Photon Source (APS) is a state-of-the-art biological solution small angle x-ray scattering (SAXS) and muscle and fiber diffraction facility. The APS upgrade (APS-U) will provide new, high flux low divergence microbeams that will significantly improve existing experimental capabilities, particularly for our time-resolved SAXS program. In addition, we have been working to develop a new highly automated temperature controlled HPLC system for SEC-SAXS, a new direct-injection batch mode SAXS autosampler that uses low sample volumes in our coflow cell, a new field-flow fractionation (FFF) SAXS system (with MALS/DLS/RI), and a unified control architecture to enable highly autonomous running for solution SAXS.
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Wang, Ning, Matthias Zeisberger, Uwe Hübner, and Markus A. Schmidt. "Nanograting-Enhanced Optical Fibers for Visible and Infrared Light Collection at Large Input Angles." Photonics 8, no. 8 (2021): 295. http://dx.doi.org/10.3390/photonics8080295.
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The efficient incoupling of light into particular fibers at large angles is essential for a multitude of applications; however, this is difficult to achieve with commonly used fibers due to low numerical aperture. Here, we demonstrate that commonly used optical fibers functionalized with arrays of metallic nanodots show substantially improved large-angle light-collection performances at multiple wavelengths. In particular, we show that at visible wavelengths, higher diffraction orders contribute significantly to the light-coupling efficiency, independent of the incident polarization, with a dominant excitation of the fundamental mode. The experimental observation is confirmed by an analytical model, which directly suggests further improvement in incoupling efficiency through the use of powerful nanostructures such as metasurface or dielectric gratings. Therefore, our concept paves the way for high-performance fiber-based optical devices and is particularly relevant within the context of endoscopic-type applications in life science and light collection within quantum technology.
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Rijah, Ban Abbas, and Iftikhar M. Ali. "Electrospun PAN@Ferrites Nanofibers for Rectifier and Humidity Devices." Iraqi Journal of Physics 22, no. 4 (2024): 139–47. https://doi.org/10.30723/ijp.v22i4.1320.
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Zinc cobalt ferrite (ZnCoFe2O4) and zinc ferrite (ZnFe2O4) were prepared using the sol-gel synthesis. composite materials, PAN@CoFe2O4 and PAN@ZnCoFe2O4, were created by combining polyacrylonitrile (PAN) polymer with ZnCoFe2O4 and ZnFe2O4. Electrospinning was used to apply thin coatings onto glass and p-Si wafers. The synthesized fibre for both pure PAN polymers and their ferrite-based composites was illustrated in Field Emission Scanning Electron Microscopy (FESEM) images. The X-ray diffraction (XRD) analysis reveals that the PAN polymer exhibits a prominent peak at a precise angle of 29. 3345°.The size of this peak remains constant in PAN composites containing ZnCoFe2O4 and CoFe2O4. Fourier transformer infrared (FTIR) shows that absorptions have stretching vibrations between metal and oxygen. Nanofiber composites display non-ohmic characteristics, as evidenced by current-voltage (I-V) tests. PAN nanofibers display conductive properties, whilst their ferrite composites demonstrate rectification behaviour at room temperature when subjected to a low applied field. For PAN NFs, there is no effect when relative humidity percentage increases and decreases, but with adding ferrite materials PAN@ZnFe2O4 and PAN@ZnCoFe2O4 where, there is a significant change in resistance when humidity increases and decreases.
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Frazer, Colleen S., and Elizabth C. Dickey. "Spatial Distribution of Crystallographic Orientational Variants in Yag-Al2O3 Directionally Solidified Eutectic Composite." Microscopy and Microanalysis 6, S2 (2000): 948–49. http://dx.doi.org/10.1017/s1431927600037235.
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YAG-A12O3 directionally solidified eutectic composites show great promise in applications requiring high temperature strength and creep resistance.’ The orientation relationships between YAG and Al2O3 have been established within the composite by use of SEM Electron Backscatter Diffraction (EBSD) and x-ray diffraction (XRD). The orientation relationships of were determined. Two related variants of A12O3 were discovered in the sample. EBSD was employed to determine the spatial distribution of the variants within the sample.The microstructure of the eutectic composite, shown in Figure 1, reflects a “chinese script” pattern, neither lamellar nor fibrous. The directionally solidified eutectic fibers, approximately 2.5 mm in diameter, were cut into disks normal to the fiber axis by a diamond saw and polished by with diamond-imbedded paper to reduce chances of phase-preferential wear. Samples used for EBSD were ion milled for 30 minutes at low power and incident angle to improve the patterns.
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Weiss, Thomas. "Instrumentation for Biological SAXS at SSRL BL4-2." Structural Dynamics 12, no. 2_Supplement (2025): A309. https://doi.org/10.1063/4.0000615.
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Small angle scattering is a powerful tool for structural investigation of matter at the nanoscale and can be applied in a variety of different ways. In structural biology and biophysics research the experimental needs range from static and time resolved solution scattering, low angle lipid and fiber diffraction to scanning imaging based on diffraction and scattering contrast. To efficiently and optimally support the various experimental requirements and ensure consistent and high quality data, automation of routine tasks and sample environments are needed. Furthermore, complementary techniques are increasingly integrated into the sample environments adding complexity to the overall setup. At the BioSAXS beamline BL4-2 at SSRL significant progress has been made in developing new and refining the existing automated sample handling methods to augment control over environmental parameters, include or improve simultaneous, complementary sample characterization methods or add handles for remote and automated operation. A dedicated, intuitive and streamlined control interface as well as connected automated data reduction and analysis pipelines ensure that the added complexity of such experiments is manageable and easily accessible to even a novice user. Here we will discuss some of the key advancements in automated beamline control and sample handling available at the BL4-2.
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Ding, Chang Kun, Bo Wen Cheng, and Qiong Wu. "Mechanical Properties and Ordered Structure of Bacterial Poly(3-Hydroxybutyrate-Co-3-Hydroxyhexanoate) Fibers Stretched after Isothermal Crystallization near Tg." Advanced Materials Research 284-286 (July 2011): 1774–77. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1774.
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Biodegradable fibers of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) were prepared by melt spinning, followed by one-step-drawing with small crystal nuclei grown after isothermal crystallization near the glass transition temperature (Tg) and annealing at room temperature under tension. This new drawing technique is a very attractive method for obtaining flexible fibers from low-molecular-weight biopolyesters produced by recombinant bacteria. The ordered structure of PHBHHx fibers was investigated by tensile measurement, scanning electron microscopy, and wide-angle X-ray diffraction (WAXD). The tensile strength of 10 times one-step-drawn fiber after isothermal crystallization increased to 100 MPa. The WAXD profiles of PHBHHx fibers showed sharp reflections corresponding to highly oriented α-form (21helix conformation) crystal.
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Yu, Q., B. Tang, C. Huang, et al. "The diffraction detector for the EMD of the CSNS." Journal of Instrumentation 16, no. 12 (2021): P12018. http://dx.doi.org/10.1088/1748-0221/16/12/p12018.
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Abstract On 23rd August 2018, the China Spallation Neutron Source (CSNS) located in Dongguan operated 4 neutron instruments. In the future, twenty neutron spectrometers will be built to provide multidisciplinary platforms for scientific research by national institutions, universities, and industries. Engineering Material Diffractometer (EMD), which will be used for strain measurements in engineering materials and components, will be constructed at the Beamline 8 in 2022. A novel thermal neutron detector, which will comply with the requirements of EMD application, is being developed. This detector will consist of 6LiF/ZnS(Ag) scintillation screens, wavelength shifting fiber (WLSF) arrays, a silicon photomultiplier (SiPM) and Application Specific Integrated Circuit (ASIC) read-out electronics. Each scintillation screen will be inclined with respect to the incident neutron beam at a grazing angle θ = 17°. Such geometry will not only improve the spatial resolution of detectors but also the neutron detection efficiency. The prototype of detector module has been tested at the neutron Beamline 20 at the CSNS. The experimental results obtained for this prototype illustrate that the pixel size of detector module is 3 mm and the detection efficiency exceeds 40% at the neutron wavelength of 1 Å. Based on these results, we design and manufacture the final version of the detector for the EMD application, which is characterized by low power consumption, highly integrated and easy to install. 70 such detectors will be installed till the end of 2021.
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Grishin, Alexander M. "Microstructure and Intrinsic Strain of Nanocrystals in Ferroelectric (Na,K)NbO3 Nanofibers." Nanomaterials 12, no. 9 (2022): 1541. http://dx.doi.org/10.3390/nano12091541.
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Densely woven highly crystallized biocompatible sodium–potassium niobate Na0.35K0.65NbO3 fibers with an average diameter of 100–200 nm and several hundreds of microns in length were sintered by the sol–gel calcination-assisted electrospinning technique. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (TEM) confirmed preferential cube-on-cube [001] orientation of nanocrystals within the fiber’s body, separated by a low angle grain boundary. The Williamson–Hall method was employed to analyze the broadening of XRD reflections and to accurately determine the size and intrinsic strain of nanocrystal fiber aggregates. The main objective of this article is to test the potential capacity of direct XRD analysis to noninvasively control crystallite size and lattice distortion in core-shell coaxial nanofibers.
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Zou, Xiang, Qingyou Liu, and Shengtao Qiu. "Electron Backscatter Diffraction Analysis of Low-Misorientation-Angle Boundary and High-Energy Boundary in the Hot-Rolled Plate of Grain-Orientated Silicon Steel." Metals 14, no. 10 (2024): 1170. http://dx.doi.org/10.3390/met14101170.
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In order to study the texture evolution and the formation of an inhomogeneous microstructure in hot-rolled plate of grain-orientated silicon steel, Fe3C (hexagonal) and ferrite phases in the subsurface layer were studied using electron backscatter diffraction. The results indicate that fiber texture (ferrite) mainly composed of {441}<104> and (110)[001] Goss oriented grains was formed at a depth of 25% of the thickness of hot-rolled plate. Matrix grains in the subsurface layer were arbitrary separated into irregular large grains (≥40 μm) and fine grains (<40 μm), and the grain boundary characteristics and texture evolution of matrix grains were studied. The results indicated that the formation of the colonies of fine grains was the result of dynamic recrystallization, and high-frequency low-misorientation-angle boundaries (0~20°) were formed between large grains (≥40 μm) and fine grains (<40 μm), which can be considered as the irregularity of large grains caused by solid-state wetting. Due to the texture evolution of large grains (≥40 μm), a large number of high-energy boundaries (20~45°) were formed between irregular large grains (≥40 μm), resulting in rapid consumption between adjacent large grains and the elongation of large grains along the rolling direction. Therefore, it can be assumed that the migration of low-misorientation-angle boundaries (0~20°) under solid-state wetting and high-energy boundaries (20~45°) are important mechanisms for non-uniform grain growth in hot-rolled plate of grain-orientated silicon steel.
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Fu, Heng, Jianwei Jiang, Jianbing Men, and Xinfu Gu. "Microstructure Evolution and Deformation Mechanism of Tantalum–Tungsten Alloy Liner under Ultra-High Strain Rate by Explosive Detonation." Materials 15, no. 15 (2022): 5252. http://dx.doi.org/10.3390/ma15155252.
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The microstructure evolution and plastic deformation mechanism of a Ta-2.5W liner under the ultra-high-strain-rate conditions generated by the explosive detonation were investigated in this study. For this purpose, a modular soft-recovery apparatus was designed to non-destructively recover the Ta-2.5W explosively formed projectile (EFP) in the ballistic endpoint. The electron backscattered diffraction (EBSD) method was employed to examine the microstructure of the Ta-2.5W liner before and after deformation. The microstructure of the recovered EFP exhibited significant grain refinement with preferred fiber texture. The theoretical computation results showed that the temperature of the EFP was in the range of 0.27–0.65 Tm. The deformation mechanism of the Ta-2.5W liner forming EFP driven by the detonation is the continuous dynamic recrystallization (CDRX) induced by high strain deformation, rather than the conventional dynamic recrystallization of nucleation and growth. The new grain structures evolve when the low-angle grain boundaries are transformed into the high-angle grain boundaries, and the specific grain refinement mechanism is the progressive rotation of subgrains near pre-existing grain boundaries.
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Hänninen, Tuomas, Eero Kontturi, Kirsi Leppänen, Ritva Serimaa, and Tapani Vuorinen. "Kraft pulping of Juniperus communis results in paper with unusually high elasticity." BioResources 6, no. 4 (2011): 3824–35. http://dx.doi.org/10.15376/biores.6.4.3824-3835.
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Juniper (Juniperus communis) is a slowly growing softwood species that has unusually high elasticity. To demonstrate the utilization of the material properties of juniper, conventional kraft pulping was used to prepare juniper pulp, whose handsheet and fiber properties were subsequently analyzed. A large number of uncooked fiber bundles remained after pulping, the screened yield was low, and kappa number high. Also the viscosity value of juniper pulp was lower than that of common industrial softwood pulps, due to the harsh pulping conditions required. Juniper fibres had thicker cell walls, smaller diameters, and shorter lengths than those of the more conventional softwood species, while the microfibril angle, which was measured by X-ray diffraction, was significantly higher (22-37°). Moreover, the strength properties of juniper pulp handsheets were lower than those of common softwood pulps. The intriguing elastic properties of juniper wood, however, were apparent in the handsheet properties. Tensile stiffness was determined to be merely half of the value typical for softwood pulps, whereas the breaking stretch was more than twice higher. Although a large-scale industrial use of juniper is not possible, one can speculate that it may be feasible to mimic its properties via transgenic modification to faster growing species.
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Wang, Yateng, Jianru Fan, Hao Zhao, et al. "Biomimetic Robust Starch Composite Films with Super-Hydrophobicity and Vivid Structural Colors." International Journal of Molecular Sciences 23, no. 10 (2022): 5607. http://dx.doi.org/10.3390/ijms23105607.
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The starch composite films (SCFs) will be one of the best alternative packaging materials to petroleum based plastic films, which mitigates white pollution and energy consumption. However, weak mechanical stability, water resistance, and dyeability has hindered the application of SCFs. Herein, a bioinspired robust SCFs with super-hydrophobicity and excellent structural colors were prepared by fiber-reinforcement and assembling SiO2/Polydimethylsiloxane (PDMS) amorphous arrays on the surface of SCFs. The properties of the designed SCFs were investigated by various methods including scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), a tensile test, contact angle (CA) test, and an optical test. The results showed that the obtained SCFs possessed a higher tensile strength (55.17 MPa) attributed to the formed abundant hydrogen bonds between the molecular chains of the starch, cellulose fiber, and polyvinyl alcohol. Benefiting from the nanostructure with rough surface which were modified by materials with low surface free energy, the contact angle and sliding angle of the film reached up to 154° and 2°, respectively. The colors which were produced by the constructive interference of the coherent scattered light could cover all of the visible regions by tuning the diameters of the SiO2 nanoparticles. The strategy in the present study not only reinforces the mechanical strength and water resistance of SCFs but also provides an environmentally friendly way to color the them, which shows unprecedented application potential in packaging materials of the starch composite films.
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Xu, Renwei, Peng Zhang, Hai Wang, et al. "Structure and Properties of a Metallocene Polypropylene Resin with Low Melting Temperature for Melt Spinning Fiber Application." Polymers 11, no. 4 (2019): 729. http://dx.doi.org/10.3390/polym11040729.
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An isotactic polypropylene (iPP-1) resin with low melting temperature (Tm) is synthesized by a metallocene catalyst and investigated for melt-spun fiber applications. The structure, thermal and mechanical properties, and feasibility of producing fibers of a commercial metallocene iPP (iPP-2) and a conventional Ziegler–Natta iPP (iPP-3) are carefully examined for comparison. Tm of iPP-1 is about 10 °C lower than the other two samples, which is well addressed both in the resin and the fiber products. Besides, the newly developed iPP-1 possesses higher isotacticity and crystallinity than the commercial ones, which assures the mechanical properties of the fiber products. Thanks to the addition of calcium stearate, its crystal grain size is smaller than those of the two other commercial iPPs. iPP-1 shows a similar rheological behavior as the commercial ones and good spinnability within a wide range of take-up speeds (1200–2750 m/min). The tensile property of fibers from iPP-1 is better than commercial ones, which can fulfill the application requirement. The formation of the mesomorphic phase in iPP-1 during melt spinning is confirmed by the orientation and crystallization investigation with wide angle X-ray diffraction (WAXD), which is responsible for its excellent processing capability and the mechanical properties of the resultant fibers. The work may provide not only a promising candidate for the high-performance PP fiber but also a deep understanding of the formation mechanism of the mesomorphic phase during fiber spinning.
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Golla, Manohar, Baku Nagendra, Christophe Daniel, Paola Rizzo, and Gaetano Guerra. "Axial Orientation of Co-Crystalline Phases of Poly(2,6-Dimethyl-1,4-Phenylene)Oxide Films." Polymers 12, no. 10 (2020): 2394. http://dx.doi.org/10.3390/polym12102394.
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Films exhibiting co-crystalline (CC) phases between a polymer host and low-molecular-mass guest molecules are relevant for many applications. As is usual for semi-crystalline polymers, axially oriented films can give relevant information on the crystalline structure, both by Wide Angle X-ray diffraction fiber patterns and by polarized Fourier-transform infrared spectroscopy. Axially oriented CC phases of poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) with 1,3,5-trimethylbenzene (mesitylene) can be simply obtained by the stretching of CC PPO films. In fact, due to the plasticization effect of this highly boiling guest, PPO orientation can occur in a stretching temperature range (170–175 °C) nearly 50 °C lower than that generally needed for PPO films (220–230 °C). This low stretching temperature range allows avoidance of polymer oxidation, as well as formation of the mesomorphic dense γ PPO phase. Axially oriented CC phases of PPO with toluene, i.e., with a more volatile guest, can be instead obtained by the stretching (in the same low temperature range: 170–175 °C) of CC PPO blend films with polystyrene.
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Perret, Edith, Konrad Jakubowski, Manfred Heuberger, and Rudolf Hufenus. "Effects of Nanoscale Morphology on Optical Properties of Photoluminescent Polymer Optical Fibers." Polymers 14, no. 16 (2022): 3262. http://dx.doi.org/10.3390/polym14163262.
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Bicomponent photoluminescent polymer optical fibers (PL-POFs) have been melt-spun and in-situ drawn to different extents. The results suggest that scattering in the sheath can effectively increase the photoluminescent dye excitation probability in the fiber core. The core/sheath PL-POFs are made of a semi-crystalline fluoropolymer sheath of low refractive index (RI) and an amorphous cycloolefin polymeric core of high RI, which is doped with a luminescent dye. The axial light emission, as well as the guiding attenuation coefficients of the core/sheath PL-POFs, have been measured using a side-illumination set-up. The incident blue laser is down-converted to red light, which is re-emitted and partially guided by the core. The axial light emission is measured at the fiber tip as a function of the distance of the illumination position to the integrating sphere. It is demonstrated that the presence of a semi-crystalline sheath significantly enhances the axial light emission and that it also lowers the attenuation coefficient, compared to the emission and guiding properties of PL core-only fibers. Additionally, the attenuation coefficient has been found to be lower in more strongly drawn PL-POFs. Wide-angle X-ray diffraction and small-angle X-ray scattering experiments reveal structural differences in differently drawn PL-POFs that can be linked to the observed differences in the optical properties.
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Prasad, M. J. N. V. "Texture Studies of Superplastically Deformed Electrodeposited Nanocrystalline Ni and Ni-P Alloy." Materials Science Forum 702-703 (December 2011): 378–81. http://dx.doi.org/10.4028/www.scientific.net/msf.702-703.378.
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Nanocrystalline Ni and Ni-P alloy with grain size down to 6 nm were processed by pulsed electrodeposition. The as-deposited materials, possessing a strong fiber texture, were tested in tension at different temperatures and strain rates. Both materials exhibited low temperature superplasticity but with significant differences in mechanical characteristics. In comparison with nano-Ni, the nano Ni-P alloy exhibited significant strain hardening in flow behavior and lower superplastic elongations at relatively low strain rates, although the grain size was finer at test temperatures with limited grain growth in nano Ni-P alloy. Texture study as a function of strain and strain rate by bulk X-ray Schultz reflection and electron back scattered diffraction (EBSD) revealed development of cube components {001} and {013} with negligible deformation texture components (Cu or brass type) and limited fraction of low angle grain boundaries (< 10 %) in superplastically deformed samples. The reasons for the formation of cube components and their influence on flow behavior of electrodeposited materials were critically analyzed. Additional microstructural investigation by transmission electron microscopy revealed dislocations movement constrained by intragranular particles, leading to strain hardening and cavitation in the nano Ni-P alloy.
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Sandim, Hugo Ricardo Zschommler, Alexandra O. F. Hayama, and Dierk Raabe. "Recrystallization Behavior of the Nickel-Based ODS Superalloy PM 1000." Materials Science Forum 558-559 (October 2007): 313–18. http://dx.doi.org/10.4028/www.scientific.net/msf.558-559.313.
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PM 1000 is a nickel-based oxide dispersion strengthened (ODS) superalloy used for high-temperature applications. The primary recrystallization of a <100>-fiber textured coarsegrained oxide dispersion strengthened nickel-based superalloy (PM 1000) has been investigated. The annealing behavior of this alloy is quite complex. Even when annealing is performed at high homologous temperatures (e.g. 0.9 Tm, Tm is the melting point), recrystallization is partial. In order to understand such a behavior, the microstructure of specimens in both the as-received, deformed, and annealed conditions has been imaged in detail using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution electron backscatter diffraction (EBSD). In the annealed state we observe a significant volume fraction of tiny crystals in the interior of the recovered grains. These tiny grains are elongated and grow mostly along the existing low angle dislocation boundaries (anisotropic growth). In the present paper we propose a twinningassisted nucleation mechanism to clarify their origin during recrystallization.
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Somashekar, R., I. H. Hall, and P. D. Carr. "The determination of crystal size and disorder from X-ray diffraction photographs of polymer fibres. 1. The accuracy of determination of Fourier coefficients of the intensity profile of a reflection." Journal of Applied Crystallography 22, no. 4 (1989): 363–71. http://dx.doi.org/10.1107/s0021889889004085.
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Methods which determine the number and disorder of lattice planes in a crystal from the Fourier cosine coefficients of the intensity profile of an X-ray reflection use only the low harmonics and require that the coefficients be normalized so that the zero harmonic is unity. Experimentally, the profiles can only be recorded over a smaller range of scattering angle than required by the theory, and it is necessary to subtract background, which is likely to be estimated with considerable error, before determining the coefficients. It is shown that with polymer fibres this causes serious errors in the normalization, and in the values of those low harmonics used in the size and disorder determination, and prevents reliable values being obtained. Methods which avoid normalization and use only high harmonics are needed. It is shown that disorder may be obtained in such a way, but not size, for which low-order normalized coefficients are essential. A method of extrapolation is described and tested which enables the accurate high harmonics to be used to improve the estimates of the low ones. Whilst this will yield more reliable values of crystal size than are obtainable from existing methods, the accuracy depends entirely on the validity of the extrapolation, which cannot be tested in many cases of interest.
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Hevilla, Víctor, Águeda Sonseca, Enrique Gimenez, Coro Echeverría, Alexandra Muñoz-Bonilla, and Marta Fernández-García. "The Incorporation of Low-Molecular Weight Poly(Mannitol Sebacate)s on PLA Electrospun Fibers: Effects on the Mechanical Properties and Surface Chemistry." Polymers 14, no. 16 (2022): 3342. http://dx.doi.org/10.3390/polym14163342.
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We offer a report on the synthesis of low-molecular weight biobased poly(mannitol sebacate) (PMS) and its functionalization with acrylate groups (PMSAc). These synthesized polyesters were blended at a low level (10 wt%) with poly (lactic acid) PLA to prepare aligned fibers by electrospinning, coupled with a rotatory collector. The obtained fibers were extensively studied by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and wide-angle X-ray diffraction (WAXS), employing synchrotron radiation. The incorporation of the PMSs on the PLA fibers did not significantly affect the fiber diameters, whereas the alignment was almost maintained. The crystallinity and thermal properties were also slightly modified with the addition of PMSs, and an increase in the degree of crystallinity and in the glass transition temperature of the blend compared to PLA was observed. Remarkably, the PLA/PMSs fibers were more ductile due to the elastomeric character of PMS, with higher values of elongation at break and tensile strengths, and a smaller Young modulus in comparison with the PLA fibers. These modifications of the properties were more noticeable in the case of the acrylated PMS, which also provided readily available functional groups at the surface for further chemical reactions, such as the Michael addition or crosslinking processes.
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Li, Juan, Honglong Zhao, Nian Zhou, et al. "Study on Microstructure of Fiber Laser Welding of CoCrCuFeNi High Entropy Alloy." Materials 15, no. 24 (2022): 8777. http://dx.doi.org/10.3390/ma15248777.
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A CoCrCuFeNi high-entropy alloy was successfully welded in this study using fiber laser welding. The effects of the welding parameters on the microstructure and mechanical properties were studied. Three zones were formed: the fusion zone, partial melting zone, and base metal. The base metal exhibited a typical dendrite structure, and the Cu element segregated in the interdendrite. The fusion zone consisted of fine equiaxed crystals and columnar crystals with the same crystalline structure as the base metal. The fusion zone exhibited minimal compositional microsegregation after laser welding. Electron backscatter diffraction results showed that the low-angle grain boundary fraction in the fusion zone increased. Furthermore, some dislocations and dislocation pile-ups were present in the fusion zone, and the densities of the dislocations and dislocation pile-ups were higher than those of the base metal. The hardness of the fusion zone was considerably higher than that of the base metal, while the ultimate tensile strength and elongation values were lower than those of the base metal for all conditions. The ultimate tensile strength and the elongation increased gradually and then decreased with increasing laser power. The maximum ultimate tensile strength exceeded that of the base metal by 90%.
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Peng, Xiaowen, Kexing Song, Yanjun Zhou, et al. "Influence of P Content on Microstructure and Texture Evolution of the Oxygen-Free Copper." Metals 12, no. 10 (2022): 1622. http://dx.doi.org/10.3390/met12101622.
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The present work aims to systematically investigate the influence of P content on the microstructure and texture evolution of oxygen-free copper during intermediate annealing and final cold rolling. The microstructure and texture evolution were studied by electron backscattered diffraction and transmission electron microscopy. With the addition of P, the grains refined and a large fraction of low angle grain boundaries (LAGBs) emerged after intermediate annealing. The texture transformed from pure metal type for pure Cu to the α-fiber texture which included brass and Goss texture as P was added. The recrystallization temperature increased with the addition of P, and refined grains after the final cold rolling process. The addition of elemental P would reduce the stacking fault energy, and then influence the transformation of the deformation and recrystallization texture of the copper. Accompanied by the evolution of the deformation texture, the recrystallization cubic texture {001}<100> was suppressed and a strong {236}<385> brass recrystallization texture emerged with the addition of elemental P after the intermediate annealing and subsequent final cold rolling process.
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Zhang, Chao, Hui Li Shao, Xue Chao Hu, and Yao Peng Zhang. "Effect of Draw Ratio on the Microstructure of Silk Fibroin/Graphene Oxide Hybrid Fibers." Materials Science Forum 898 (June 2017): 2214–23. http://dx.doi.org/10.4028/www.scientific.net/msf.898.2214.
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In order to fabricate high performance artificial silk, hybrid fibers were dry spun from regenerated silk fibroin (RSF) aqueous solution mixed with graphene oxide (GO) nanosheets. The influence of draw ratio on the microstructure and mechanical properties of RSF/GO hybrid fibers was studied through Fourier transform infrared spectroscopy (FT-IR), synchrotron radiation wide-angle X-ray diffraction, Raman spectroscopy and mechanical testing. The results showed that with increasing draw ratio, both amorphous phase and mesophase of the dry-spun artificial fiber gradually converted to crystals. The orientation of crystals and mesophase changed slightly at low draw ratio, but increased significantly at draw ratios of 3 and 4X. The β-sheet content of silk fibroin and the disorder degree of GO sheets in the fibers also increased with the increase of draw ratio. The initial modulus, breaking strength and breaking energy of the hybrid fibers achieved great improvement at a draw ratio of 4X. The structure evolution of the RSF/GO hybrid fibers may benefit the understanding of the structure-property relationship of other composite fibers.
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Niu, Hongqing, Mengying Zhang, Ang Li, et al. "Microstructure evolution and properties of polyimide fibers containing trifluoromethyl units." High Performance Polymers 32, no. 1 (2019): 39–46. http://dx.doi.org/10.1177/0954008319846922.
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A series of copolyimide (co-PI) fibers containing trifluoromethyl units were successfully obtained on the molecular design of 3,3′,4,4′-biphenyltetracarboxylic dianhydride, p-phenylenediamine, and 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (HFBAPP) via a widely utilized two-step wet-spinning method. Significant variations on the microstructures and properties of the resulting co-PI fibers were observed after the incorporation of HFBAPP moieties. The tensile strength and initial modulus of the fibers decreased from 0.70 GPa to 0.38 GPa and from 69.63 GPa to 9.60 GPa, respectively. However, the dielectric permittivity decreased from 3.62 to 2.85 in the frequency of 10 MHz as a result of the incorporation of trifluoromethyl units. Two-dimensional wide-angle X-ray diffraction showed that the fibers exhibited highly oriented molecular alignments along the fiber direction and low lateral packing degree in the transverse direction. In addition, the co-PI fibers possessed excellent thermal–oxidative stabilities with the 5% weight loss temperature ranging from 532°C to 552°C under nitrogen atmosphere and the glass transition temperature ranging from 312°C to 330°C.
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Sponza, Deli̇a Teresa, and Ruki̇ye Özteki̇n. "Photoremoval of Oil, DOC, DSS, Toluene and m-Xylene from a Petrochemical Industry via Cellulose Nanocomposites Derivated from Textile Wastes." International Journal of Environmental Engineering and Development 3 (June 18, 2025): 71–99. https://doi.org/10.37394/232033.2025.3.7.
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In this study a nanocomposite namely cellulose nanocrystals (CNCs) was produced under laboratory conditions from textile wastes to remove the pollutants [oil, dissolved organic carbon (DOC), dissolved suspended solids (DSS), toluene and m-xylene] present in a petrochemical industry wastewater (PCI ww). With the aim of reducing environmental pollution and promoting economic circularity, textile wastes such as fibres, yarn clippings, fabric remnants from factory cuts, and new garments has been shown to be a viable material for nanocellulose extraction, its low cost, high amount in landflls. Nanocellulose extraction from textile waste was performed in two-stage process. Firstly, a purification process for the removal of non-cellulosic components is performed for cellulose fibre isolation then alkaline treatment and bleaching stages were applied. Afterwards, nanocellulose is extracted from cellulose fibrils. SEM analysis showed that CNCs presented a homogeneous structure. FTIR assays exhibited a band at 3422 cm−1 which is attributed to the hydroxyl groups and the band at 2889 cm−1 indicates the carboxylic acids. The XRD pattern of CNCs exibited two main diffraction peaks at 2θ angles of 8° and 18.9°. TGA of the samples exhibited low degrees of carboxyl functionalization. This reduced thermal stability and the degradation temperature. The DTG data for cellulose showed highest extent of carboxyl content in the CNCs samples. The effects of some operational conditions such as increasing of photoremoval time, increasing pH values, increasing pollutant concentrations (oil, DOC, DSS, toluene and m-xylene) and increasing CNCs nanocomposite concentrations on the maximum yields of PCI ww pollutants were investigated. Maximum 99.30% oil, 99.10% DOC, 99.52% DSS, 95.64% toluene, and 99.05% m-xylene removal efficiencies were observed at 100 mg/l CNC nanocomposites concentration, in PCI ww, after 150 min photoremoval time, at pH=7.0, at 1000 mg/l pollutant concentrations, and at 25oC, respectively. Nanocellulose obtained from textile wastes is seen as a sufficient and promising alternative to synthetic polymers, with the advantage of being obtained from renewable and cheap resources and also being used in the production of adequate nanocomposites.
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Wan, Ruru, Xiaoli Sun, Zhongjie Ren, Huihui Li та Shouke Yan. "Orientation of Poly(ε-caprolactone) in Its Poly(vinyl chloride) Blends Crystallized under Strain: The Role of Strain Rate". Materials 13, № 24 (2020): 5655. http://dx.doi.org/10.3390/ma13245655.
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The blends of high and low molecular weights poly(ε-caprolactone) (PCL) with poly(vinyl chloride (PVC) were prepared. The samples before and after the crystallization of PCL were uniaxially stretched to different draw ratios. The orientation features of PCL in a stretched crystalline PCL/PVC blend and crystallized from the amorphous PCL/PVC blends under varied strains were studied by wide-angle X-ray diffraction (WAXD). It was found that a uniaxial stretching of crystalline PCL/PVC blend with high molecular weight PCL results in the c-axis orientation along the stretching direction, as is usually done for the PCL bulk sample. For the stretched amorphous PCL/PVC blend samples, the crystallization of high molecular weight PCL in the blends under a draw ratio of λ = 3 with a strain rate of 6 mm/min leads to a ring-fiber orientation. In the samples with draw ratios of λ = 4 and 5, the uniaxial orientation of a-, b-, and c-axes along the strain direction coexist after crystallization of high molecular weight PCL. With a draw ratio of λ = 6, mainly the b-axis orientation of high molecular weight PCL is identified. For the low molecular weight PCL, on the contrary, the ring-fiber and a-axis orientations coexist under a draw ratio of λ = 3. The a-axis orientation decreases with the increase of draw ratio. When the λ reaches 5, only a poorly oriented ring-fiber pattern has been recognized. These results are different from the similar samples stretched at a higher strain rate as reported in the literatures and demonstrate the important role of strain rate on the crystallization behavior of PCL in its blend with PVC under strain.
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Salas-Reyes, A. E., I. Mejía, and J. M. Cabrera. "Influence of Nb Microaddition on Microstructure and Texture Evolution in a Fe-21Mn-1.3Al-1.5Si-0.5C TWIP Steel under Uniaxial Hot-Tensile Conditions." MRS Advances 2, no. 61 (2017): 3797–803. http://dx.doi.org/10.1557/adv.2017.600.
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ABSTRACTAdvanced high-strength steels as Twinning Induced Plasticity (TWIP) steels have been developed using microalloying elements and subsequent thermo-mechanical processing techniques. Moreover, under hot-working conditions, these steels undergo significant microstructural changes as a result of preferred crystallographic orientation (texture) of grains. In order to evaluate this behavior, one non-microalloyed and other single Nb-microalloyed TWIP steels were melted in an induction furnace and cast into metal and sand molds. Samples with austenitic grain sizes between 400 and 2000 µm were deformed at 800 °C and strained at a constant strain rate of 10-3 s-1, and deformation state was examined by means of electron backscatter diffraction (EBSD) technique near to the fracture tip. It was found that non-microalloyed TWIP steel solidified in both metal and sand mold exhibits dynamically recrystallized grains. On the other hand, Nb microaddition has a strong influence in TWIP steel retarding the onset of recrystallization kinetics, showing low angle sub-structured grains. Furthermore, it was possible identifying the crystallographic orientation of grains using the inverse pole figures (IPF) and the orientation distribution function (ODF). Weak cube {001}<100> recrystallization and E{111}<110> γ-fiber deformation textures components were detected.
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Fang, Xiao-Hui, Su-Hui Chen, Lan-Lin Yi, et al. "Synthesis of Si-Based High-Efficiency and High-Durability Superhydrophilic-Underwater Superoleophobic Membrane of Oil–Water Separation." Materials 14, no. 10 (2021): 2628. http://dx.doi.org/10.3390/ma14102628.
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Oil pollution is caused by the frequent discharge of contaminated industrial wastewater and accidental oil spills and is a severe environmental and health concern. Therefore, efficient materials and processes for effective oil–water separation are being developed. Herein, SiO2-Na2SiO3-coated stainless steel fibers (SSF) with underwater superoleophobic and low-adhesion properties were successfully prepared via a one-step hydrothermal process. The modified surfaces were characterized with scanning electron microscopy (SEM), and contact angle measurements to observe the surface morphology, confirm the successful incorporation of SiO2, and evaluate the wettability, as well as with X-ray diffraction (XRD). The results revealed that SiO2 nanoparticles were successfully grown on the stainless-steel fiber surface through the facile hydrothermal synthesis, and the formation of sodium silicate was detected with XRD. The SiO2-Na2SiO3-coated SSF surface exhibited superior underwater superoleophobic properties (153–162°), super-hydrophilicity and high separation efficiency for dichloromethane–water, n-hexane–water, tetrachloromethane–water, paroline–water, and hexadecane–water mixtures. In addition, the as-prepared SiO2-Na2SiO3-coated SSF demonstrated superior wear resistance, long-term stability, and re-usability. We suggest that the improved durability may be due to the presence of sodium silicate that enhanced the membrane strength. The SiO2-Na2SiO3-coated SSF also exhibited desirable corrosion resistance in salty and acidic environments; however, further optimization is needed for their use in basic media. The current study presents a novel approach to fabricate high-performance oil–water separation membranes.
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Lima, C. R. R. C., R. J. S. Lima, A. C. C. Bandeira, et al. "Alterations promoted by acid straightening and/or bleaching in hair microstructures." Journal of Applied Crystallography 56, no. 4 (2023): 1002–14. http://dx.doi.org/10.1107/s1600576723005599.
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Human hair is a biopolymer constituted mainly of keratin intermediate filaments, lipids, pigments and water. Cosmetic treatments usually interact with the hair at the molecular level, inducing changes in its components and modifying the physicochemical and mechanical properties of the fibers. Here, the effect of acid straightening on the morphology and ultrastructure of Caucasian hair was investigated by a group of complementary experimental methods: wide-, small- and ultra-small-angle X-ray scattering; high-resolution 3D X-ray microscopy; quasi-elastic neutron scattering and inelastic neutron scattering; thermogravimetry–mass spectrometry; and differential scanning calorimetry (DSC). X-ray diffraction patterns showed that acid straightening associated with a flat iron (∼180°C) changed the cortex of the fiber, shown by denaturation of the intermediate filaments (measured by DSC). The increase in the spacing of the lipid layers and the observation of the dehydration behavior of the fiber provided indications that water may be confined between these layers, while neutron spectroscopy showed alterations in the vibration mode of the CH2 groups of the lipids and an increase of the proton (H+) mobility in the hair structure. The latter may be associated with the extremely low pH of the formulation (pH ≃ 1). Additionally, this investigation showed that bleached hair (one-time bleached) is more damaged by the action of acid straightening than virgin hair, which was shown by a threefold increase in the percentage of total porosity of the tresses. The obtained results demonstrate that the investigation approach proposed here can provide very important thermodynamic and structural information on induced changes of hair structure, and certainly can be applied for the evaluation of the action mode and efficiency of cosmetic treatments.
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Bras, W., G. R. Mant, G. E. Derbyshire, et al. "Real-Time Simultaneous Wide- and Small-Angle Fibre Diffraction." Journal of Synchrotron Radiation 2, no. 2 (1995): 87–92. http://dx.doi.org/10.1107/s090904959401469x.
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Nave, C., J. R. Helliwell, P. R. Moore, et al. "Facilities for solution scattering and fibre diffraction at the Daresbury SRS." Journal of Applied Crystallography 18, no. 6 (1985): 396–403. http://dx.doi.org/10.1107/s0021889885010615.
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The small-angle scattering facility at Daresbury has been constructed for diffraction studies of a wide range of naturally occurring and synthetic materials. The high brightness of the SRS is combined with focusing optics, resulting in exposure times that can be two or three orders of magnitude less than those required on a conventional source. Spacings of 2000 Å in the vertical direction and 300 Å in the horizontal direction can be observed, while the resolution between diffraction orders is 5000 and 600 Å. In addition, preliminary results have been obtained on a double-crystal diffractometer that has a resolution, in one dimension, of better than 26 000 Å. For high-angle fibre diffraction studies, a camera with pinhole collimation has been constructed. Examples from solution scattering and fibre diffraction are used to illustrate the performance of these facilities.
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Birkholz, M. "Modelling of diffraction from fibre texture gradients in thin polycrystalline films." Journal of Applied Crystallography 40, no. 4 (2007): 735–42. http://dx.doi.org/10.1107/s0021889807027240.
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Crystallographic textures in thin polycrystalline films typically exhibit a rotational symmetry,i.e.they occur as a fibre texture with the texture pole being orientated in the direction of the substrate normal. As a further characteristic of thin-film textures, it was often observed that the degree of preferred orientation increases with increasing thickness. It is shown in this work how a fibre texture gradient may be modelled in kinematical X-ray diffraction and which effects it has on the intensity mapping of theIHKLreflection, when theHKLpole is the fibre axis. A general expression forIHKLis derived for a depth-dependent fibre texture that is based on the finite Laplace transform of the texture distribution. The concept is outlined for the cosnψ function to model the tilt-angle dependence of intensity, with the parameterndenoting the degree of texture. It is found that the measured intensity distribution sensitively depends on the ratio of texture gradient over X-ray attenuation coefficient. For particular cases, it is found that the maximum intensity may occur for non-zero tilt angles and thus arise at a different tilt angle from the pole of the fibre texture.
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Jumahat, Aidah, Constantinos Soutis, Nor Merlisa Ali, and Jamaluddin Mahmud. "Fibre Misalignment Measurement of Nanomodified-Unidirectional Carbon Fibre Laminates." Applied Mechanics and Materials 393 (September 2013): 200–205. http://dx.doi.org/10.4028/www.scientific.net/amm.393.200.
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This paper investigates the effect of nanosilica on the fibre waviness or misalignment angle distribution of carbon fibre reinforced polymer composite unidirectional laminates. The quality of the laminates was evaluated using image analyzer technique. The polished specimens were examined using Polyvar B-met optical microscope and analysed using KSRUN ZEISS software. The effect of 3, 7 and 13 vol.% nanosilica on the fibre misalignment angle distribution was determined. The results showed that, the fabricated laminates have average fibre volume fractionVfof 42%, low fibre waviness distribution (averageφo= 2.5o) and less than 1% void content. This implies that the fabrication technique, which was employed in the current work, successfully produced good quality laminates. The presence of nanosilica results in a narrow fibre angle distribution in the HTS40/828 laminate.
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Ohta, Noboru, Toshihiko Oka, Katsuaki Inoue, Naoto Yagi, Satoru Kato, and Ichiro Hatta. "Structural analysis of cell membrane complex of a hair fibre by micro-beam X-ray diffraction." Journal of Applied Crystallography 38, no. 2 (2005): 274–79. http://dx.doi.org/10.1107/s002188980403403x.
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The cell membrane complex in the cuticle of a human hair fibre or a rat whisker is composed of three layers, that is, β, δ and β layers. The X-ray diffraction technique is a powerful tool to investigate the pathway of aqueous molecules and ions across the cuticle. Small-angle scattering experiments using a micro X-ray beam, which can be applied to a cuticle of 5 µm thickness, provide the structural information on the cell membrane complex without interference from other structures. Taking into account the variation of thickness in the δ and β layers, the overall features of the diffraction profile in a small-angle region can be explained satisfactorily. The method makes it possible to analyse the structure of β, δ and β layers without assuming an ambiguous background in the diffraction profile, and was used for the analysis of a human hair fibre and a rat whisker. In a rat whisker, the X-ray diffraction was stronger and the variation in the layer thickness smaller than in a human hair fibre. This may be due to the fact that the rat whisker had not been washed with soap or cosmetically treated, whereas the variation may depend on the lipids or the proteins that each species naturally has. It is proposed that the method represents convenient tool for quantitative analysis to estimate the thickness of δ and β layers in the cell membrane complex.
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Simpson, L. H., Mark Shotton, and Trevor Forsyth. "Processing of DNA High-Angle Fibre Diffraction Patterns using the CCP13 Suite." Fibre Diffraction Review 3, no. 3 (1994): 31. http://dx.doi.org/10.1382/s19940331.
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