Journal articles: 'Flame filament'

1

Li, Xiang Hong, Jun Ying Zhang, and Jun Ma. "Development of Flame Retardant and Antistatic Fabric." Advanced Materials Research 1035 (October 2014): 106–10. http://dx.doi.org/10.4028/www.scientific.net/amr.1035.106.

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Polysulfonamide Aramid 1313 blended siro-spun yarns and silver-coated filament are used to weave flame retardant and antistatic fabrics. The effect of fabric weave and silver-coated filament content on flame retardant property and antistatic property was discussed. Two-factor analysis of variance shows that fabric weave and filament content have little effect on fabric flame retardant property, while they affect fabric antistatic property considerably. Fitting curve of antistatic property and filament content relationship was also established.

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Hwang, Jeo, Dongin Park, Subin Kim, and Dongho Rie. "A Study on the Flame-Retardant Performance of Recycled Paper Building Materials Manufactured by 3D Printer." Sustainability 14, no. 8 (April 16, 2022): 4798. http://dx.doi.org/10.3390/su14084798.

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The increase in non-face-to-face lifestyles due to COVID-19 worldwide have shown an increase in delivery services. The number of parcels in 2020 was 3.373 billion, an increase of 20.9% from 2.788 billion in 2019. This phenomenon increased delivery box waste. Against this background, this study attempted to develop building materials from the recycling of delivery boxes. In this study, the self-developed WC (wet cellulose) 3D printer confirmed the standardization and uniform performance of the sample by filling the material supply cylinder with cellulose filaments and spraying the composite material through a 10 mm nozzle. The cellulose filament for a WC 3D printer is based on cellulose extracted from wastepaper, and a cellulose filament composite material is used by mixing additives. After manufacturing a specimen using the WC 3D printer, a reliability test for the flame-retardant performance of the material was conducted according to the ISO 11925-2 test method. As a result of the experiment, flame-retardant performance was confirmed at a 40 wt% or greater ceramic binder content. In addition, the WC 3D printer achieved accurate test results by producing specimens with uniform physical properties. In addition, we confirmed that 3D-printed WC can be used to develop customized building materials that can prevent fire spread.

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Goss, L. P., V. Vilimpoc, B. Sarka, and W. F. Lynn. "Thin-Filament Pyrometry: A Novel Thermometry Technique for Combusting Flows." Journal of Engineering for Gas Turbines and Power 111, no. 1 (January 1, 1989): 46–52. http://dx.doi.org/10.1115/1.3240226.

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A novel technique is described for making temperature measurements in a combusting flow. The technique, Thin-Filament Pyrometry, is based on the blackbody emission of a small ceramic filament (15 μm), which is introduced into the flow field under study. Because the emission along the entire length of the filament is recorded, the complete spatial temperature distribution is measured. The temporal response of the filament is ∼ 700 Hz under ambient conditions. To demonstrate the capabilities of the technique in a combusting flow, a H2-N2 jet diffusion flame was studied. The evolution of the large-scale buoyancy-driven structures at low Reynolds numbers was followed by this technique.

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GÜNAYDIN, Gizem Karakan, Mine AKGÜN, Ayça GÜRARDA, Erhan Kenan ÇEVEN, and Bülent ASLAN. "INVESTIGATIONOF FRICTION COEFFICIENTOF DRAPERY FABRICS TREATED WITH DIFFERENT RATIO OF FLAME RETARDANT." TEXTEH Proceedings 2019 (November 5, 2019): 52–57. http://dx.doi.org/10.35530/tt.2019.12.

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As the security precautions with respect to new standards for the furnishing textiles in big platforms such as concert, theatre halls have increased, flame retardancy has become one of the vital required property for drapery fabrics. However, those kind of additional treatment processes may lead to some differences in fabric properties such as friction which should be considered for the consumers. This study aims to evaluate the influence of using different ratio of flame retardant chemicals (g/l) on friction coefficient of drapery fabrics. For this purpose, nine types of fabrics composed of three different weft density (9, 11, 13 threads/cm) were selected. The warp yarns were selected as 400/200 denier/filament while the weft yarns were selected as 800 /200 denier/filament textured micro polyester yarns. Three levels for flame retardant (0, 60 and 90 g/l) were determined as the finishing processes. After the dobby fabrics were woven and exposed to finishing treatments; Friction coefficient values were recorded with Labthink Param MXD-02. ANOVA tests were performed in order to evaluate the significant effect of weft density and flame retardant chemical ratio on friction properties of drapery fabrics. Additionally, SNK tests were conducted for the comparison of means of friction values of drapery fabrics produced at different weft density also of the samples treated with different flame retardant chemical ratio. Experimental results revealed that structural parameters and the finishing processes were influential factors on the surface frictional characteristics of the fabrics. It was clearly observed that surface friction coefficients of drapery fabrics decreased due to the flame retardant process.

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Kolibaba, Thomas J., Aman Nigam, Bruce L. Tai, and Jaime C. Grunlan. "Environmentally Benign Flame Retardant Polyamide‐6 Filament for Additive Manufacturing." Macromolecular Materials and Engineering 306, no. 9 (July 2, 2021): 2100245. http://dx.doi.org/10.1002/mame.202100245.

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Kong, Chengdong, Zhongshan Li, Marcus Aldén, and Andreas Ehn. "Stabilization of a turbulent premixed flame by a plasma filament." Combustion and Flame 208 (October 2019): 79–85. http://dx.doi.org/10.1016/j.combustflame.2019.07.002.

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Eskiyapar, E., H. K. Kaynak, H. İ. Çelik, and E. Sarıoğlu. "A STUDY ON ENHANCING THE FLAME RETARDANCY OF POLYPROPYLENE YARN WITH BORON COMPOUNDS." TEXTEH Proceedings 2021 (September 22, 2021): 378–84. http://dx.doi.org/10.35530/tt.2021.22.

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Functional properties such as; water resistance, flame retardancy, antibacterial efficiency etc. are required from textile products. One of the most commonly demanded products among functional textile products is the flame-retardant textiles. In this study, it is aimed to produce polypropylene filament yarn with permanent flame retardancy functionality by adding boron compound, which is Anhydrous disodium tetraborate powder (particle size < 38 micron), to the fiber structure during melt spinning process. In this study two different yarn samples are produced with anhydrous disodium tetraborate content by mass ratios of 2% and 5%. A control polypropylene filament yarn sample is also produced with no additive. By this way, three samples are produced by a conventional BCF polypropylene melt spinning machine with the same production parameters. Then, three knitted fabric samples were produced flat knitting machine. Limiting Oxygen Index (LOI) and vertical flammability tests were applied to the samples. According to results an important level of increase for LOI value is obtained with the sample which has 2% boron compound additive. Nevertheless, there is not a consistent effect of increasing boron content in yarn structure for LOI value. The reason of this situation may be resulted due to the uneven distribution of the boron compound in the yarn structure because of the particle size.

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Li, Helong, Wei Chu, Hongwei Zang, Huailiang Xu, Ya Cheng, and See Leang Chin. "Critical power and clamping intensity inside a filament in a flame." Optics Express 24, no. 4 (February 9, 2016): 3424. http://dx.doi.org/10.1364/oe.24.003424.

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Vasiljević, Jelena, Marija Čolović, Ivan Jerman, and Barbara Simončič. "Recent Advances in Production of Flame Retardant Polyamide 6 Filament Yarns." TEKSTILEC 61, no. 2 (June 27, 2018): 136–48. http://dx.doi.org/10.14502/tekstilec2018.61.136-148.

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Patil, Arun Y., N. R. Banapurmath, Sumukh E. P., Manojkumar V. Chitawadagi, T. M. Yunus Khan, Irfan Anjum Badruddin, and Sarfaraz Kamangar. "Multi-Scale Study on Mechanical Property and Strength of New Green Sand (Poly Lactic Acid) as Replacement of Fine Aggregate in Concrete Mix." Symmetry 12, no. 11 (November 3, 2020): 1823. http://dx.doi.org/10.3390/sym12111823.

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Polylactic acid (PLA) has made inroads in the commercial market segment with many unique characteristics. To list a few, such as tenacity, low flame rate, moisture regain percentage, loss of ignition percentage, combustion heat, UV resistance, elastic recovery, and higher melting point, make PLA a predominant material in the commercial market. This study is an attempt to test the feasibility of PLA’s mechanical property and strength aspects with cement mix. An article published on biodegradability aspects backed up by the essential preliminary strength and physical test results is discussed in detail in this manuscript. The work focuses on the multi-scale study along with mechanical properties and strengths to evaluate the elemental characteristics. Thermo gravimetric analysis revealed that PLA would hold inclusion into construction applications either in granular form or filament. Differential Scanning Calorimetry (DSC) found that PLA in filament form is the best inclusion material for construction applications. However, fiber’s tenacity has to be checked, as currently available filaments in the market do not have high tenacity value. From EDX(Energy-dispersive X-ray Spectroscopy) reports, 30% inclusion of PLA as a replacement for fine aggregate has constituent members as Calcium carbonate(CaCO3), Silica(SiO2), and Wollastonite (CaK) resulted in the best composition among the rest. FESEM images revealed that proper gradation in size, PLA granular form’s rough surface, or filament form would enhance the mechanical/physical behavior or even PLA’s chemical behavior.

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Li, Chunyan, Xinjie Zhou, Canghao Yang, Hui Li, Lili Yu, and Benhua Fei. "EFFECTS OF DIFFERENT FLAME RETARDANT TREATMENTS ON THE COMBUSTIBILITY OF BAMBOO FILAMENT." WOOD RESEARCH 66(2): 2021 66, no. 2 (April 30, 2021): 255–66. http://dx.doi.org/10.37763/wr.1336-4561/66.2.255266.

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Bamboo filaments were treated with boric acid and borax (the mass ratio of 1:1, the concentration of 20%) with four different treatment methods including atmospheric immersion, cold and hot bath immersion, vacuum impregnation and vacuum-pressure impregnation. The different treatment methods on the boron loading were analyzed and the corresponding flame resistance of bamboo filaments were evaluated by the cone analysis. The results showed that suitable treatment method with optimized processing indexes, such as hot and cold bath immersion in the condition of 100°C/2 h and 20°C/2 h with 3 cycles, was more credible to accelerate the percentages of boron loading in the bamboo filaments, and the lowest result was found in the samples with vacuum impregnation. Compared to the untreated samples, the heat and smoke release would be decreased significantly, especially for the samples with the promising hot and cold treatment, and promising pressure treatment, attributed to the more stable boron fixed in the bamboo filaments.

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12

Lee, Shin-Hee. "Fabrication and Characteristics of Flame Retardant Fabric Developed by using Bicomponent Filament." Textile Coloration and Finishing 25, no. 2 (June 27, 2013): 110–17. http://dx.doi.org/10.5764/tcf.2013.25.2.110.

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13

Čolović, Marija, Jelena Vasiljević, Žiga Štirn, Nataša Čelan Korošin, Matic Šobak, Barbara Simončič, Andrej Demšar, Giulio Malucelli, and Ivan Jerman. "New sustainable flame retardant DOPO-NH-functionalized polyamide 6 and filament yarn." Chemical Engineering Journal 426 (December 2021): 130760. http://dx.doi.org/10.1016/j.cej.2021.130760.

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14

SATO, Yuya, Masahisa SHINODA, and Hiroshi YAMASHITA. "G601 Verification of High-Speed Flame Propagation Mechanism by Vortex Filament Soliton." Proceedings of the Fluids engineering conference 2010 (2010): 587–88. http://dx.doi.org/10.1299/jsmefed.2010.587.

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15

Li, Ziting, Jinming Chen, Zhaoxiang Liu, Jinping Yao, Jianping Yu, Yi Li, Fengyi Rong, Pengfei Wang, Hongqiang Xie, and Ya Cheng. "Nonintrusive temperature measurement of a combustion field by femtosecond laser-induced third harmonic generation." Journal of Physics B: Atomic, Molecular and Optical Physics 55, no. 7 (April 6, 2022): 075401. http://dx.doi.org/10.1088/1361-6455/ac60ad.

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Abstract We report a comparative experimental investigation of femtosecond laser-induced third harmonic generation (THG) in an ethanol flame and in air. It was found that the third harmonic (TH) signal produced in the presence of a combustion field can be greatly enhanced, in comparison to that generated in air, and that the enhancement factor depends strongly on the experimental parameters, such as the focal length, relative position of the flame and filament, and laser repetition frequency. Moreover, by replacing the flame with a point temperature controller, a similar signal enhancement of THG was observed, and the TH signal exhibited a nonlinear growth with the heating temperature. Further analysis indicated that the observed enhancement of THG originates from the suppression of Gouy-phase-induced destructive interference due to the disturbed gas density under high-temperature heating. The high sensitivity of the TH signal to the combustion temperature helps formulate an effective and straightforward approach to achieve nonintrusive temperature measurements in the combustion field.

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Li, Suyu, Yanhua Li, Zhe Shi, Laizhi Sui, He Li, Qingyi Li, Anmin Chen, Yuanfei Jiang, and Mingxing Jin. "Fluorescence emission induced by the femtosecond filament transmitting through the butane/air flame." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 189 (January 2018): 32–36. http://dx.doi.org/10.1016/j.saa.2017.08.006.

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Lee, Shin-Hee. "Dyeing of Flame Retardant Polyester Fabric developed by using Low-melting-point Bicomponent Filament." Fashion & Textile Research Journal 15, no. 3 (June 30, 2013): 467–76. http://dx.doi.org/10.5805/sfti.2013.15.3.467.

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Sood, Bhanu, and Michael Pecht. "Conductive filament formation in printed circuit boards: effects of reflow conditions and flame retardants." Journal of Materials Science: Materials in Electronics 22, no. 10 (August 11, 2011): 1602–15. http://dx.doi.org/10.1007/s10854-011-0449-z.

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Lin, Cherng-Yuan, Tze-Chin Pan, and Che-Shiung Cheng. "A Comparative Study on the Combustion Characteristics of Burning Droplets of Marine Fuel Oils." Journal of Ship Research 38, no. 04 (December 1, 1994): 349–53. http://dx.doi.org/10.5957/jsr.1994.38.4.349.

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An experimental study conducted on a single oil droplet suspended on a quartz filament is carried out to investigate the effects of droplet size and heating time on the combustion characteristics of marine fuel oils. Fuel oils A and C, which approximate ASTM Nos. 2 and 6 fuel oils, respectively, are considered in this study primarily due to their frequent applications in marine power plants. The properties of these fuels are widely different; marine diesel fuel oil A is a distillate oil of miscible multi-components while heavy fuel oil C is known as a residual oil containing considerable amounts of immiscible matter. The combustion phenomena are observed by cinematography. The results show that the influences of droplet size and heating time on the combustion characteristics of flame length, flame appearance, soot, ignition delay, and overall burning rate vary for these two fuel oils to a significant extent. The reasons for these variations are discussed.

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20

Pauzin, S., A. Giovannini, and B. Bédat. "Thin filament infrared pyrometry: instantaneous temperature profile measurements in a weakly turbulent hydrocarbon premixed flame." Experiments in Fluids 17, no. 6 (October 1994): 397–404. http://dx.doi.org/10.1007/bf01877042.

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Dambach, Erik M., Brent A. Rankin, Timothée L. Pourpoint, and Stephen D. Heister. "Temperature Estimations in the Near-Flame Field Resulting from Hypergolic Ignition Using Thin Filament Pyrometry." Combustion Science and Technology 184, no. 2 (February 2012): 205–23. http://dx.doi.org/10.1080/00102202.2011.627403.

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Betz, Stefan, Fabian Köster, and Vasileios Ramopoulos. "Energy and Time Efficient Microwave Curing for CFRP Parts Manufactured by Filament Winding." Materials Science Forum 825-826 (July 2015): 741–48. http://dx.doi.org/10.4028/www.scientific.net/msf.825-826.741.

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Process time reduction and energy/cost savings are usually in the focus of production process improvements. New technologies provide possibilities to achieve significant enhancements for relevant operation figures.Curing cycle times for CFRP manufacturing depend on several requirements: Type of resin, requested glass transition temperature, used equipment and energy source as well as sample size, weight, fibre volume ratio, fibre orientation etc. Conventional methods are mostly based on heat conduction while microwaves offer a selective and volumetric heating of the samples. Process time reduction and energy saving are the positive effects of the microwave curing technology.This paper will give an overview of the current status of this process technology not only focussing on technical aspects but also covering the process and economic effects.This work has been performed under the German BMBF project 02PJ2131, FLAME under the program Energy Efficient Light Weight Construction.

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Rusmirović, Jelena, Jela Galović, Marija Kluz, Srdja Perković, Saša Brzić, Marica Bogosavljević, Aleksandar Milojković, and Tihomir Kovačević. "Using potential of filament-wound carbon/glass polymeric composites as rocket motor thermal insulation." Polymers and Polymer Composites 29, no. 9_suppl (November 2021): S1541—S1554. http://dx.doi.org/10.1177/09673911211056787.

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The study aim is to develop hybrid filament-wound polymeric composites based on flame retardant polyester resin (UPe) and multi-layer structured glass or combined carbon and glass fibers for use as ablative thermal insulation of rocket motor by wet filament winding technique. The composites have a multi-layered structure consisting of two layers of carbon (CF) or glass woven fabric (GF) and one layer of carbon or glass direct roving (CR or GR, respectively), repeated in three cycles. Structural analysis, performed using FTIR spectroscopy and dynamical-mechanical analysis, confirm highly polymerized network. Lower values of the tanδ peak height indicate improved interfacial adhesion between carbon/glass fibers and UPe. The improvements of thermal insulation index of 37% and erosion rate of 38.6% at 180°C are achieved for combined carbon/glass fiber–based composite compared to the neat UPe. Tensile and interlaminar shear properties are investigated according to the fiber orientation and the highest values of tensile and interlaminar shear strengths are obtained for composites with longitudinal orientation, 417.48 MPa and 22.30 MPa, respectively. Compared to the neat UPe, which degrades after 50 s at 3000°C, the composites are stable up to 192 s.

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Franco-Urquiza, Edgar Adrián, Yael Ramírez Escamilla, and Perla Itzel Alcántara Llanas. "Characterization of 3D Printing on Jute Fabrics." Polymers 13, no. 19 (September 22, 2021): 3202. http://dx.doi.org/10.3390/polym13193202.

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This work evaluates the feasibility to manufacture polylactic acid (PLA) composites using jute fiber fabrics. For characterization, PLA-fused filament was successfully deposed onto jute fabrics to print dog-bone tensile specimens (Type I specimen from ASTM D638). The jute fabrics were chemically modified, treated with flame retardant additives, and sprayed with aerosol adhesive to improve the mechanical properties of PLA/Jute fabric composites. The elastic modulus and the strength of PLA were higher than PLA composites, and the plastic deformation of the PLA composites was slightly lower than PLA. Tomography scans revealed the fabrics were well oriented and some adherence between jute fabrics and PLA. Viscoelastic properties of PLA composites resulted in the reduction in storage modulus and the reduction in intensity in the damping factor attributed to segmental motions with no variations in the glass transition temperature. Flame retardant and spray adhesive on jute fabrics promoted better response to time of burning than PLA and PLA with modified fibers. The results presented in this work lead to the need for a more detailed investigation of the effect of plant fiber fabrics as reinforcement of 3D printed objects for industrial applications.

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Shoshin, Y., V. N. Kurdyumov, and L. P. H. De Goey. "Numerical and experimental studies of torus-like flame around the vortex filament in a premixed reactant flow." Combustion Science and Technology 191, no. 1 (May 15, 2018): 81–94. http://dx.doi.org/10.1080/00102202.2018.1452492.

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Jiang, Shenglong, Guangxin Liao, Dingding Xu, Fenghua Liu, Wen Li, Yuchuan Cheng, Zhixiang Li, and Gaojie Xu. "Mechanical properties analysis of polyetherimide parts fabricated by fused deposition modeling." High Performance Polymers 31, no. 1 (January 16, 2018): 97–106. http://dx.doi.org/10.1177/0954008317752822.

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Polyetherimide (PEI) is a kind of high-performance polymer, which possesses a high glass transition temperature ( Tg), excellent flame retardancy, low smoke generation, and good mechanical properties. In this article, PEI was applied in the fused deposition modeling (FDM)–based 3-D printing for the first time. The entire process from filament extrusion to printing was studied. It was observed that the filament orientation and nozzle temperature were closely related to the mechanical properties of printed samples. When the nozzle temperature is 370°C, the mean tensile strength of FDM printing parts can reach to 104 MPa, which is only 7% lower than that of injection molded parts. It can be seen that the 0° orientation set of samples show the highest storage modulus (2492 MPa) followed by the 45° samples, and the 90° orientation set of samples show the minimum storage modulus (1420 MPa) at room temperature. The above results indicated that this technique allows the production of parts with adequate mechanical performance, which does not need to be restricted to the production of mock-ups and prototypes. Our work broke the limitations of traditional FDM technology and expanded the types of material available for FDM to the high-temperature engineering plastics.

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Freitas, J. A., J. E. Butler, and U. Strom. "Photoluminescence studies of polycrystalline diamond films." Journal of Materials Research 5, no. 11 (November 1990): 2502–6. http://dx.doi.org/10.1557/jmr.1990.2502.

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The photoluminescence spectra of polycrystalline diamond films prepared by filament assisted chemical vapor deposition are dominated by a defect band with a strong zero phonon line near 1.68 eV and weak phonon replicas at lower energies. The 1.68 eV line is blucshifted from the 1.675 eV zero phonon line associated with the neutral vacancy in bulk diamond. The line shape and position of the 1.68 eV line are shown to depend on substrate material (Si, Mo, Ni). The 1.68 eV emission for Ni and Mo substrates is interpreted in terms of the stress shifted and broadened neutral vacancy emission. The broader 1.68 eV line observed for Si substrates may indicate the additional effects of Si absorption by the diamond films. Films prepared by an oxygen-acetylene flame technique exhibit two additional luminescence bands with zero phonon lines at 1.95 and 2.16 eV. These lines have been tentatively assigned to nitrogen-vacancy complexes. The temperature dependence (6 K–300 K) of the luminescence of a free-standing diamond film, which had been deposited on a molybdenum substrate, is comparable to similar observations reported for bulk diamond. We have also observed a strong dependence of the PL spectra radially across a given combustion film and associated this with details of the flame chemistry.

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Picone, J. M., and J. P. Boris. "Vorticity generation by shock propagation through bubbles in a gas." Journal of Fluid Mechanics 189 (April 1988): 23–51. http://dx.doi.org/10.1017/s0022112088000904.

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We present a new theoretical model of ‘late-time’ phenomena related to the interaction of a planar shock with a local, discrete inhomogeneity in an ambient gas. The term ‘late-time’ applies to the evolution of the inhomogeneity and the flow field after interaction with the incident shock has ceased. Observations of a shock propagating through a bubble or a spherical flame have exhibited or implied the formation of vortex structures and have showed continual distortion of the bubble or flame. Our theory shows that this is due to the generation of long-lived vorticity at the edge of the discrete inhomogeneity. The vorticity interacts with itself through the medium of the fluid, and, depending on the geometry of the discrete inhomogeneity, can roll up into vortex filaments or vortex rings. To verify and amplify this theoretical description, we use numerical solutions of the fluid equations for conservation of mass, momentum, and energy to study the interaction of a weak shock with a cylindrical or spherical bubble. The simulated bubble has either a higher or lower density than the ambient gas. In this way, the calculations provide insights into the effects of both geometry and distortion of the local sound speed. The Mach number of the shock is 1.2, the ambient gas is air, and the pressure is 1 atmosphere. Because of the simple geometry of each bubble, the vorticity generated at the boundary rolls up into a vortex filament pair (cylindrical bubble) or a vortex ring (spherical bubble). The structural features and timescales of the phenomena observed in the calculations agree closely with recent experiments of Haas & Sturtevant, in which helium and Freon bubbles were used to provide the local departures from ambient density. The discussion of results includes a survey of alternative numerical methods, sources of uncertainty in velocities of interfaces or structures, as derived from the laboratory and numerical experiments, and the relationship of our analysis to other theories.

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Poletaev, N. L. "The Influence of Oxygen Content of Air on the Flame Velocity Through Cellulose Dust and Along Cellulose Filament." Пожаровзрывобезопасность 21, no. 4 (August 2012): 8–12. http://dx.doi.org/10.18322/pvb.2012.21.04.8-12.

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Li, Wei, and Jingxiu Wang. "Filament Activity Associated With an Umbral Flare." International Astronomical Union Colloquium 167 (1998): 401–4. http://dx.doi.org/10.1017/s0252921100048004.

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AbstractAn umbral flare in NOAA 6223 was observed at Huairou Solar Observing Station of Beijing Astronomical Observatory. Vigorous filament activity took place in association with this umbral flare. Several filaments formed and/or disappeared, leaving the magnetic neutral lines pointing to or rooted in the P spot in which the umbral flare occurred. We describe the observed configuration and evolution of the vector magnetic fields in the photosphere, and Doppler velocity patterns in the chromosphere during the course of the umbral flare and related filament activity.

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Zhang, Q. M. "Simultaneous transverse oscillations of a coronal loop and a filament excited by a circular-ribbon flare." Astronomy & Astrophysics 642 (October 2020): A159. http://dx.doi.org/10.1051/0004-6361/202038557.

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Aims. The aim of this study is to investigate the excitation of kink oscillations in coronal loops and filaments, by analyzing a C3.4 circular-ribbon flare associated with a blowout jet in active region 12434 on 2015 October 16. Methods. The flare was observed in ultraviolet and extreme-ultraviolet wavelengths by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory (SDO) spacecraft. The line-of-sight (LOS) magnetograms of the photosphere were observed by the Helioseismic and Magnetic Imager on board SDO. Soft X-ray fluxes of the flares in 0.5−4 and 1−8 Å were recorded by the GOES spacecraft. Results. The flare excited small-amplitude kink oscillation of a remote coronal loop. The oscillation lasted for ≥4 cycles without significant damping. The amplitude and period are 0.3 ± 0.1 Mm and 207 ± 12 s. Interestingly, the flare also excited transverse oscillation of a remote filament. The oscillation lasted for ∼3.5 cycles with decaying amplitudes. The initial amplitude is 1.7−2.2 Mm. The period and damping time are 437−475 s and 1142−1600 s. The starting times of simultaneous oscillations of coronal loop and filament were concurrent with the hard X-ray peak time. Though small in size and short in lifetime, the flare set off a chain reaction. It generated a bright secondary flare ribbon (SFR) in the chromosphere, remote brightening (RB) that was cospatial with the filament, and intermittent, jet-like flow propagating in the northeast direction. Conclusions. The loop oscillation is most probably excited by the flare-induced blast wave at a speed of ≥1300 km s−1. The excitation of the filament oscillation is more complicated. The blast wave triggers secondary magnetic reconnection far from the main flare, which not only heats the local plasma to higher temperatures (SFR and RB), but produces jet-like flow (i.e., reconnection outflow) as well. The filament is disturbed by the secondary magnetic reconnection and experiences transverse oscillation. These findings provide new insight into the excitation of transverse oscillations of coronal loops and filaments.

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Molodensky, M. M., and J. C. Vial. "On the Motion of Eruptive Prominences." International Astronomical Union Colloquium 144 (1994): 349–52. http://dx.doi.org/10.1017/s0252921100025586.

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AbstractThe increase of current in filaments can be evidenced by the variation of its twist. We show two examples of such a current increase, the last stage of which is the filament eruption and the flare. We suggest a theory of the equilibrium and the eruptive motion including the interaction of the filament current with the magnetic fields of the active region and the mirror current. We take into account the curvature of filament.

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Ramachandran, Koushik, Fuhan Liu, Nitesh Kumbhat, Baik-Woo Lee, Venky Sundaram, Rao Tummala, and Mark Wilson. "Reliability Studies in Advanced Halogen-free Organic Laminates for Ultra-fine Pitch 3D Packaging." International Symposium on Microelectronics 2010, no. 1 (January 1, 2010): 000829–35. http://dx.doi.org/10.4071/isom-2010-tha3-paper1.

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High I/O density and green materials are the two major drivers of package substrates for flip-chip and 3D IC packaging. Future organic laminate substrates will require 5–25 μm lines and spaces and through-package-via (TPV) pitch of 50–100 μm. This ultra fine pitch requirement will lead to serious substrate failures due to electrochemical migration and conductive anodic filament (CAF). Therefore, there is a need to develop new halogen-free materials and investigate their reliability in ultra-fine pitch applications. This work focuses on four areas, 1) Advanced halogen-free materials, 2) Surface insulation resistance (SIR) in fine lines and spaces, 3) Conductive anodic filament (CAF) in fine-pitch TPVs, and 4) Flip-chip interconnection reliability. The substrate materials selected for this study include resin formulations that incorporate halogen-free flame retardants onto the polymer backbone. The SIR was studied on substrates with 50 μm spaced copper traces and CAF was studied with TPVs of 150 μm and 400 μm spacing. In both the tests, the halogen-free substrates were observed to show better electrochemical migration resistance in comparison to brominated FR-4. Flip-chip reliability was studied by subjecting the test substrates to Thermal Cycling Test (TCT), Unbiased-Highly Accelerated Stress Test (U-HAST) and High Temperature Storage (HTS) test. Scanning Acoustic Microscopy (C-SAM) analysis and electrical resistance measurements were performed after each of the reliability tests. The test substrates passed 200 hours of HTS, 96 hours of HAST and 2000 cycles in TCT respectively. The flip-chip reliability results indicate that these materials have the potential for replacing the conventional halogenated substrates for high density packaging applications.

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Callebaut, Dirk K., and Valentine I. Makarov. "On the Relationship Between Current and Magnetic Field in Ring-Filaments." International Astronomical Union Colloquium 167 (1998): 111–14. http://dx.doi.org/10.1017/s0252921100047394.

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AbstractThere is a type of filament that forms closed contours encircling regions of one polarity of magnetic field, while the surrounding region has the opposite polarity. One distribution of ring-filaments has sizes 2R = 40,000 to 160,000 km with the maximum around 100,000 km; the other distribution (with filaments and filament channels) has bigger sizes, with a maximum around 300,000 km. At low and mid latitudes the radial component Brs (radial for the Sun) in the region outlined by filaments varies from 50 to 100 gauss, while the longitudinal component Bϕ, varies from 10 to 30 gauss. The total current inside the filament is 1010 – 1011 A, the ratio R/a ≈ 5 to 10, the magnetic flux crossing the surface is ≈ 1021 – 1022Mx; the magnetic energy is ≈ 1029 – 1031erg. Polar ring-filaments at latitudes 60° – 80° are related to the polar magnetic field reversal and the quasi-flare processes at the poles during the field reversal. Correlation between Brs and Bϕ, for the polar filament bands cannot be satisfactorily explained. A theoretical model using the conservation laws is used to study the relations between the various fields, currents, etc. of shrinking polar ring-filaments and their evolution. According to this theory ring-filaments should rise higher above the photosphere when shrinking. However, observations show that the height lowers. Presumably the discrepancy is due to the lack of dissipation in the model.

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Martin, S. F., O. Panasenco, O. Engvold, and Y. Lin. "The link between CMEs, filaments and filament channels." Annales Geophysicae 26, no. 10 (October 15, 2008): 3061–66. http://dx.doi.org/10.5194/angeo-26-3061-2008.

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Abstract. We present a broad concept for the build-up to eruptive solar events which needs to be tested in future observational and theoretical research. In this concept an eruptive solar event consists of a coronal mass ejection, a filament eruption, a cavity around the filament, and a flare. In our picture, the initial energy source must be external to this eruptive system but also feed into it. Among all eruptive events the common denominator is a filament channel with canceling magnetic fields along a primary polarity reversal boundary. We find that magnetic reconnection at or close to the photosphere is the only interpretation of canceling fields to date that is consistent with observations of filament channels. This reconnection serves to transfer magnetic flux from the photosphere into the chromosphere and corona along polarity reversal boundaries and concurrently initiates the building of a filament channel. Magnetic flux, in excess of that needed to sustain the filament channel, goes into building a filament magnetic field that is always aligned with the polarity reversal boundary and the channel magnetic field. The filament magnetic field remains separated from overarching coronal magnetic fields by the magnetic field of the cavity. The magnetic flux being transported upward from the photosphere/chromosphere carries streams of plasma into the corona along the filament magnetic field. However, the flowing and counterstreaming filament mass also slowly drains out of the field and thereby leaves behind new strands of cavity magnetic field with little or no associated mass. When the build-up of magnetic pressure in the filament and cavity magnetic fields exceeds that of the overlying coronal loops, the coronal loops, the filament and the cavity together begin an observable slow rise which can last a few hours to many days before rapid onset and ejection with a solar flare. We suggest that this process can be accelerated by any number of external triggering mechanisms which serve as catalysts to cause the impending eruption to happen earlier than it otherwise would occur.

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Zhou, Chengrui, Yuandeng Shen, Xinping Zhou, Zehao Tang, Yadan Duan, and Song Tan. "Sympathetic Filament Eruptions within a Fan-spine Magnetic System." Astrophysical Journal 923, no. 1 (December 1, 2021): 45. http://dx.doi.org/10.3847/1538-4357/ac28a0.

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Abstract It is unclear whether successive filament eruptions at different sites within a short time interval are physically connected or not. Here, we present the observations of successive eruptions of a small and a large filament in a tripolar magnetic field region whose coronal magnetic field showed as a fan-spine magnetic system. By analyzing the multiwavelength observations taken by the Solar Dynamic Observatory and the extrapolated three-dimensional coronal magnetic field, we find that the two filaments resided respectively in the two lobes that make up the inner fan structure of the fan-spine magnetic system. In addition, a small fan-spine system was also revealed by the squashing factor Q map, which located in the east lobe of the fan structure of the large fan-spine system. The eruption of the small filament was a failed filament eruption, which did not cause any coronal mass ejection (CME) except for three flare ribbons and two post-flare-loop systems connecting the three magnetic polarities. The eruption of the large filament not only caused similar post-flare-loop systems and flare ribbons, as observed in the small filament eruption, but also a large-scale CME. Based on our analysis results, we conclude that the two successive filament eruptions were physically connected, in which the topology change caused by the small filament eruption is thought to be the physical linkage. In addition, the eruption of the small fan-spine structure further accelerated the instability and violent eruption of the large filament.

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Yang, Bo, Jiayan Yang, Yi Bi, Junchao Hong, and Zhe Xu. "Formation of a Solar Filament by Magnetic Reconnection, Associated Chromospheric Evaporation, and Subsequent Coronal Condensation." Astrophysical Journal Letters 921, no. 2 (November 1, 2021): L33. http://dx.doi.org/10.3847/2041-8213/ac31b6.

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Abstract We present the first observation of a solar filament formed by magnetic reconnection, associated chromospheric evaporation, and subsequent coronal condensation. Driven by shearing motion during flux emergence, a sequential tether-cutting reconnection process occurred and resulted in an M1.3 confined flare accompanied by the formation of a sigmoid structure. It is found that the flare had conjugate compact footpoint brightenings, which correspond to the footpoints of the sigmoid. Furthermore, observational evidence of explosive evaporation is well diagnosed at the conjugate footpoint brightenings in the impulsive phase of the flare. After the flare, continuous cool condensations formed at about the middle section of the sigmoid and then moved in opposite directions along the sigmoid, eventually leading to the formation of the filament. These observations suggest that magnetic reconnection can not only form the magnetic field structure of the filament but also heat the chromospheric footpoints during their formation and drive chromospheric evaporation. As a result, the heated chromospheric plasma may be evaporated into the magnetic field structure of the filament, where the accumulated hot plasma might suffer from thermal instability or nonequilibrium, causing catastrophic cooling and coronal condensation to form the cool, dense material of the filament. This observation lends strong support to the evaporation–condensation model and highlights the crucial role of magnetic reconnection in forming both the magnetic field structure and the cool, dense material of the filaments.

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Jiang, Zhaohui, Zengge Guo, Congcong Pu, Jing Wang, Zhao Jia, Changfa Xiao, and Shulin An. "Preparation and properties of melt-spinning fluorinated ethylene propylene fibres." High Performance Polymers 29, no. 4 (May 27, 2016): 476–83. http://dx.doi.org/10.1177/0954008316651689.

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In this work, a novel fibre, fluorinated ethylene propylene (FEP) filament, was fabricated by melt-spinning. In addition, the properties of FEP fibres were investigated through apparent morphological observation, tensile testing, dry-hot shrinkage, differential scanning calorimetry, thermogramitric analysis (TGA) and Fourier transform infrared spectroscopy. Apparent morphological observation shows that FEP fibres present circular cross-sections and smooth surfaces. Just like the conventional fibres prepared by melt-spinning, such as poly (ethylene terephthalate) (PET) and polyamide 6, the stress–strain curves of FEP fibres show obvious stress yield points. The elastic recovery ratio of FEP fibres (80%) is much greater than that of polytetrafluoroethylene (PTFE) fibres (40%), endowing FEP textiles good wrinkle resistance. When FEP fibres are deposited in flame, smoke and droplets do not appear but shrinkage does occur. After treatment in hot air, the breaking strength of FEP fibres decreases, but the elongation at break increases. The melting temperature of FEP fibres is as closely high as that of the PET fibres, while the crystallization temperature is much higher, which puts forward greater challenges for FEP spinning. Compared with PTFE fibres, the crystallinity and the melting temperature of FEP fibres are much lower. TGA results demonstrate that FEP fibres present excellent thermal stability that is as stable as that of the PTFE fibres.

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Dai, Jun, Zhentong Li, Ya Wang, Zhe Xu, Yanjie Zhang, Leping Li, Qingmin Zhang, Yingna Su, and Haisheng Ji. "A Partial Filament Eruption in Three Steps Induced by External Magnetic Reconnection." Astrophysical Journal 929, no. 1 (April 1, 2022): 85. http://dx.doi.org/10.3847/1538-4357/ac4fbe.

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Abstract We present an investigation of partial filament eruption on 2012 June 17 in the active region NOAA 11504. For the first time, we observed the vertical splitting process during the partial eruption with high-resolution narrowband images at 10830 Å. The active filament was rooted in a small δ-sunspot of the active region. Particularly, it underwent the partial eruption in three steps, i.e., the precursor, the first eruption, and the second eruption, while the latter two were associated with a C1.0 flare and a C3.9 flare, respectively. During the precursor, slow magnetic reconnection took place between the filament and the adjoining loops that also rooted in the δ-sunspot. The continuous reconnection not only caused the filament to split into three groups of threads vertically but also formed a new filament, which was growing and accompanied brightening took place around the site. Subsequently, the growing filament erupted together with one group splitted threads, resulted in the first eruption. At the beginning of the first eruption, a subsequent magnetic reconnection occurred between the erupting splitted threads and another ambient magnetic loop. After about 3 minutes, the second eruption occurred as a result of the eruption of two larger unstable filaments induced by the magnetic reconnection. The high-resolution observation provides a direct evidence that magnetic reconnection between filament and its ambient magnetic fields could induce the vertical splitting of the filament, resulting in partial eruption.

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Vasiljević, Jelena, Andrej Demšar, Mirjam Leskovšek, Barbara Simončič, Nataša Čelan Korošin, Ivan Jerman, Matic Šobak, Gregor Žitko, Nigel Van de Velde, and Marija Čolović. "Characterization of Polyamide 6/Multilayer Graphene Nanoplatelet Composite Textile Filaments Obtained Via In Situ Polymerization and Melt Spinning." Polymers 12, no. 8 (August 10, 2020): 1787. http://dx.doi.org/10.3390/polym12081787.

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Studies of the production of fiber-forming polyamide 6 (PA6)/graphene composite material and melt-spun textile fibers are scarce, but research to date reveals that achieving the high dispersion state of graphene is the main challenge to nanocomposite production. Considering the significant progress made in the industrial mass production of graphene nanoplatelets (GnPs), this study explored the feasibility of production of PA6/GnPs composite fibers using the commercially available few-layer GnPs. To this aim, the GnPs were pre-dispersed in molten ε-caprolactam at concentrations equal to 1 and 2 wt %, and incorporated into the PA6 matrix by the in situ water-catalyzed ring-opening polymerization of ε-caprolactam, which was followed by melt spinning. The results showed that the incorporated GnPs did not markedly influence the melting temperature of PA6 but affected the crystallization temperature, fiber bulk structure, crystallinity, and mechanical properties. Furthermore, GnPs increased the PA6 complex viscosity, which resulted in the need to adjust the parameters of melt spinning to enable continuous filament production. Although the incorporation of GnPs did not provide a reinforcing effect of PA6 fibers and reduced fiber tensile properties, the thermal stability of the PA6 fiber increased. The increased melt viscosity and graphene anti-dripping properties postponed melt dripping in the vertical flame spread test, which consequently prolonged burning within the samples.

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Ossenkopf-Okada, V., and R. Stepanov. "Measuring the filamentary structure of interstellar clouds through wavelets." Astronomy & Astrophysics 621 (December 19, 2018): A5. http://dx.doi.org/10.1051/0004-6361/201731596.

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Context. The ubiquitous presence of filamentary structures in the interstellar medium asks for an unbiased characterization of their properties including a stability analysis. Aims. We propose a novel technique to measure the spectrum of filaments in any two-dimensional data set. By comparing the power in isotropic and anisotropic structures we can measure the relative importance of spherical and cylindrical collapse modes. Methods. Using anisotropic wavelets we can quantify and distinguish local and global anisotropies and measure the size distribution of filaments. The wavelet analysis does not require any assumptions on the alignment or shape of filaments in the maps, but directly measures their typical spatial dimensions. In a rigorous test program, we calibrate the scale dependence of the method and test the angular and spatial sensitivity. We apply the method to molecular line maps from magneto-hydrodynamic (MHD) simulations and observed column-density maps from Herschel observations. Results. When applying the anisotropic wavelet analysis to the MHD data, we find that the observed filament sizes depend on the combination of magnetic-field-dominated density–velocity correlations and radiative transfer effects. This can be exploited by observing tracers with different optical depth to measure the transition from a globally ordered large-scale structure to small-scale filaments with entangled field lines. The unbiased view to Herschel column-density maps does not confirm a universal characteristic filament width. The map of the Polaris Flare shows an almost scale-free filamentary spectrum up to the size of the dominating filament of about 0.4 pc. For the Aquila molecular cloud the range of filament widths is limited to 0.05–0.2 pc. The filaments in Polaris show no preferential direction in contrast to the global alignment that we trace in Aquila. Conclusions. By comparing the power in isotropic and anisotropic structures we can measure the relative importance of spherical and cylindrical collapse modes and their spatial distribution.

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Zhang, Yan, Xiaoli Yan, Jincheng Wang, Qiaoling Li, Liheng Yang, and Zhike Xue. "A Double-decker Filament Formation Driven by Sunspot Rotation and Magnetic Reconnection." Astrophysical Journal 933, no. 2 (July 1, 2022): 200. http://dx.doi.org/10.3847/1538-4357/ac7391.

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Abstract In this paper, through analyzing data from the Solar Dynamics Observatory (SDO) and the Global Oscillation Network Group (GONG), we present a study on the formation of a double-decker filament in NOAA Active Region 12665 from 2017 July 8 to 14. We find that magnetic reconnection occurs between two smaller filaments to form a longer filament. According to the evolution of the leading sunspot, it is obvious that the sunspot experiences a continuous rotation around its umbra. During the period from 03:00 UT on July 11 to 10:00 UT on July 14, the average speed of sunspot rotation is about 3.°7 hr–1. The continuous rotation of sunspot stretches the filament and results in the formation of a reversed S-shaped filament. Due to the motion of the magnetic field and internal magnetic reconnection, the filament splits into two branches and forms a double-decker filament structure. In the process of filament separation, internal magnetic reconnection can also accelerate the filament separation. Nonlinear force-free field extrapolation indicates that there are two magnetic flux ropes, which are consistent with the observed results. Eventually, the upper filament erupts and produces an M-class flare and a halo coronal mass ejection.

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Martins, Raíssa Carvalho, Simone Pereira da Silva Ribeiro, Michelle Jakeline Cunha Rezende, Regina Sandra Veiga Nascimento, Marco Antonio Chaer Nascimento, Marcos Batistella, and José-Marie Lopez-Cuesta. "Flame-Retarding Properties of Injected and 3D-Printed Intumescent Bio-Based PLA Composites: The Influence of Brønsted and Lewis Acidity of Montmorillonite." Polymers 14, no. 9 (April 21, 2022): 1702. http://dx.doi.org/10.3390/polym14091702.

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The influence of processing intumescent bio-based poly(lactic acid) (PLA) composites by injection and fused filament fabrication (FFF) was evaluated. A raw (ANa) and two acidic-activated (AH2 and AH5) montmorillonites were added to the intumescent formulation, composed by lignin and ammonium polyphosphate, in order to evaluate the influence of the strength and the nature (Brønsted or Lewis) of their acidic sites on the fire behavior of the composites. The thermal stability and the volatile thermal degradation products of the composites were assessed. The injected and 3D-printed composites were submitted to cone calorimeter (CC), limit oxygen index (LOI), and UL-94 flammability tests. A similar tendency was observed for the injected and 3D-printed samples. The high density of strong Lewis sites in AH2 showed to be detrimental to the fire-retarding properties. For the CC test, the addition of the intumescent composite reduced the peak of heat released (pHRR) in approximately 49% when compared to neat PLA, while the composites containing ANa and AH5 presented a reduction of at least 54%. However, the addition of AH2 caused a pHRR reduction of around 47%, close to the one of the composite without clay (49%). In the LOI tests, the composites containing ANa and AH5 achieved the best results: 39% and 35%, respectively, for the injected samples, and 35 and 38% for the 3D-printed samples. For the composite containing AH2 the LOI values were 34% and 32% for injected and 3D-printed samples, respectively. Overall, the best performance in the flammability tests was achieved by the composites containing clays with only weak and moderate strength acidic sites (ANa and AH5).

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Rosen, B. H., B. W. MacLeod, and M. R. Simpson. "Accumulation and Release of Geosmin during the Growth Phases of Anabaena circinalis (Kutz.) Rabenhorst." Water Science and Technology 25, no. 2 (January 1, 1992): 185–90. http://dx.doi.org/10.2166/wst.1992.0051.

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Anabaena circinalis (Kutz.) Rabenhorst was isolated during a taste and odor episode characterized by high concentrations of geosmin, with raw water containing up to 45 ng geosmin/L. This species has been successfully cultured with sustained geosmin synthesis on both sterile river water and defined medium. Gas chromatography of cellular extracts and closed-loop stripping of growth media indicated that this organism produces geosmin and not 2-methylisoborneol (MIB). With cultures we examined the changes in cell-associated geosmin, chlorophyll and released geosmin during exponential and stationary growth phases of Anabaena. Cell-associated geosmin samples were collected daily from cultures and filtered onto a polycarbonate filter, extracted in acetone, and quantified by capillary gas Chromatograph using flame ionization detection. Media-associated geosmin was quantified from algae-free filtrates from each culture concentrated by closed-loop stripping and analyzed as above. Cell-associated geosmin averaged at 8 × 10−6 ng geosmin/cell in the exponential phase and dropped to 2.5 × 10−6 ng geosmin/cell in the stationary phase of growth. The loss in cell-associated geosmin was accompanied by an increase in geosmin released into the media. Media-associated geosmin reached 12 ng/mL in the stationary phase. Apparently cell lysis in the stationary phase caused the release of cell-associated geosmin into the media. Cell-associated geosmin was closely correlated with filament number (average r2 from 4 experiments =0.96) during the exponential growth phase and was correlated with chlorophyll a (average r2 from 3 experiments =0.95).

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Du, James Xianxing. "Bilingual Biblical Etymology - Origin of Language." International Journal of Linguistics 12, no. 5 (September 20, 2020): 30. http://dx.doi.org/10.5296/ijl.v12i5.17716.

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Multilingual mutual match in biblical etymology is a secret of civilization and definitive evidence for creation, presented for the first time in history. 恐terror is error to carry ark by two poles工to battlefield, 謬mistake is to take ark marked by cherubim to shed blood , 奉 dedication has two dactyl hands to offer cattle as tithe, 祝blessing is sibling兄, 嬰Infant is financial貝to fiancé and fiancée, 音Sound has Son童, sonic is in prison , 辨to distinguish digital hands is related to Jonah’s debate辯, 諒to forgive is related to whale鲸and capital京, and黥criminal label has capital after殳killing Abel from穀grain offering. Biblical books such as Genesis, Exodus, Leviticus and Jonah are astonishingly validated by bilingual mutual match in biblical etymology. Bilingual mutual match links退quit to quite很, 骄pride to bridge桥, 宴banquet to bank堰, 霉mould to plum blossom梅, 園garden to garment衣, 悛repent to paternal公Adam, 悔remorse to maternal母Eve, 濁opacity to optic目, 稠dense to seeds禾on altar口, 脯sausage to use用, 恿urge to courage勇, religion to grill and logged legal book, 忿anger and rage to revenge in segregation分, and朝morning to mourn悼. Many affixes are presented, such as nat+vowel of native, innate and nation as tone, wh as human near water, 乍restricted motion in炸explosion, migration to circumvent giant巨, a motion affix , 夭human to flee, 匽to hide Moses in basket near Nile bank堰, 兆water and fire, co-carriage of ark and altar, 用/甬/甫as altar’s service, and as star. Known affixes such as com, tech, 巴, , 貝and曼curtain also match biblical etymology. 爸father is to thaw fat肥in faith at thermal altar, 疤scar has sacred worshiper巴, and relative is related to altar. Creatures have biblical etymology. Clove is created to resemble cloud, tendril resembles spilled blood lines on tent’s curtain, 藤vine has vineyard , vessel舟, fire and Noah’s hands , dolphin has phonic ultrasound, and elephant has elevated sound. The systematic bilingual match in biblical etymology spans all categories. Wednesday is water condensation and seed day, 奥/謎 mystery has star , 樂music, smile and laugh have semi and halves, 球sphere/globe is ephod/robe裘’s pomegranate, textile has to exit in exile, filament has flame, fiber has fire, desperation is to tear apart dress, inheritance and heritage繼are to tear attire and fragment斷garment, 亵blasphemy is to take执divided clothes for military to humiliate Son, satire has attire, mock is blocked sunlight, Corpse is sacred Sarco on cross, 讽sarcasm is Sarco and crazy疯to validate Jesus, oath is to heat theological offering cut with hatchet, family has flame for kin to kindle, meal in flame is alumni, to incite is to incinerate, to instigate is to ignite, to stimulate is meal at flame of altar, health is to heat wheat at altar, tomb is mobility, and town is own tone and own tower, solving the etymology of numerous words. In conclusion, the entire languages of English and China and also words in additional ancient languages must have been divinely created in etymology to predestinedly and mutually match each other, and equally astonishingly, match bible, as the origin of language.

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ZHANG, CAIJUAN, HUI GUO, XINJIE ZHOU, LILI YU, HUI LI, and ZHI-BIN YANG. "EFFECTS OF DIFFERRENT BORON-BASED FLAME RETARDANTS ON THE COMBUSTIBILITY OF BAMBOO FILAMENTS." Wood Research 67, no. 2 (April 19, 2022): 221–30. http://dx.doi.org/10.37763/wr.1336-4561/67.2.221230.2.

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In this study, eight types of boron-based flame retardants were performed to evaluate theeffects of different boron components on the combustibility of the bamboo filaments. Disodium octaborate tetrahydrate, boric acid/borax, and nano-ZnBO4were used as the active flame retardant components. Besides, other inorganic flame retardants including nano-SiO2and ammonium polyphosphate (APP) were also introduced in order to increase the flame retardant of these boron-based components. The combustibility of the bamboo filaments treated with different flame retardants were evaluated by cone calorimeter analysis. Theresults showed that the flame retardants including the heat release and smoke release resistance of the bamboo filaments with different boron-based components and nano-SiO2or APP, could be significantly improved, especially, in the samples treated with the compound flame retardant composed of boric acid, borax and nano-SiO2, which was attributed to the synergistic effect of these flame retardant components.

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Firsov, Alexander, Konstantin V. Savelkin, Dmitry A. Yarantsev, and Sergey B. Leonov. "Plasma-enhanced mixing and flameholding in supersonic flow." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2048 (August 13, 2015): 20140337. http://dx.doi.org/10.1098/rsta.2014.0337.

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The results of experimental study of plasma-based mixing, ignition and flameholding in a supersonic model combustor are presented in the paper. The model combustor has a length of 600 mm and cross section of 72 mm width and 60 mm height. The fuel is directly injected into supersonic airflow (Mach number M =2, static pressure P st =160–250 Torr) through wall orifices. Two series of tests are focused on flameholding and mixing correspondingly. In the first series, the near-surface quasi-DC electrical discharge is generated by flush-mounted electrodes at electrical power deposition of W pl =3–24 kW. The scope includes parametric study of ignition and flame front dynamics, and comparison of three schemes of plasma generation: the first and the second layouts examine the location of plasma generators upstream and downstream from the fuel injectors. The third pattern follows a novel approach of combined mixing/ignition technique, where the electrical discharge distributes along the fuel jet. The last pattern demonstrates a significant advantage in terms of flameholding limit. In the second series of tests, a long discharge of submicrosecond duration is generated across the flow and along the fuel jet. A gasdynamic instability of thermal cavity developed after a deposition of high-power density in a thin plasma filament promotes the air–fuel mixing. The technique studied in this work has weighty potential for high-speed combustion applications, including cold start/restart of scramjet engines and support of transition regime in dual-mode scramjet and at off-design operation.

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Uddin, Wahab, and V. K. Verma. "Eruption of a Twisted Filament and Associated Phenomena." International Astronomical Union Colloquium 167 (1998): 338–41. http://dx.doi.org/10.1017/s0252921100047874.

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AbstractIn this paper we present CCD observations between February 14–20, 1994 and analysis of the giant twisted filament evolved in the active region NOAA 7671. The dynamic eruption of the filament was accompanied by a major flare (3B/M4), CME, long duration type II, IV radio bursts, great microwave bursts, a long duration soft X-ray burst, SIDs, strong geomagnetic storms and a very energetic proton flare. We analysed and estimated the twist, length, volume, mass and energy associated with filament system between February 14 and 20, 1994. The present study shows that the magnetic energy required for the solar flare came from the filament system associated with the solar flare and associated phenomena.

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Chandra, Ramesh, Pascal Démoulin, Pooja Devi, Reetika Joshi, and Brigitte Schmieder. "Filament Eruption Driving EUV Loop Contraction and Then Expansion above a Stable Filament." Astrophysical Journal 922, no. 2 (December 1, 2021): 227. http://dx.doi.org/10.3847/1538-4357/ac2837.

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Abstract We analyze the observations of EUV loop evolution associated with the filament eruption located at the border of an active region (AR). The event SOL2013-03-16T14:00 was observed with a large difference in view point by the Solar Dynamics Observatory and Solar Terrestrial Relations Observatory. The filament height is fitted with the sum of a linear and exponential function. These two phases point to different physical mechanisms such as tether-cutting reconnection and a magnetic instability. While no X-ray emission is reported, this event presents classical eruption features like separation of double ribbons and the growth of flare loops. We report the migration of the southern foot of the erupting filament flux rope due to the interchange reconnection with encountered magnetic loops of a neighboring AR. Parallel to the erupting filament, a stable filament remains in the core of the AR. The specificity of this eruption is that coronal loops, located above the nearly joining ends of the two filaments, first contract in phase, then expand and reach a new stable configuration close to the one present at the eruption onset. Both contraction and expansion phases last around 20 minutes. The main difference with previous cases is that the PIL bent about 180° around the end of the erupting filament because the magnetic configuration is at least tripolar. These observations are challenging for models that interpreted previous cases of loop contraction within a bipolar configuration. New simulations are required to broaden the complexity of the configurations studied.

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Schmieder, Brigitte, Cristina Mandrini, Ramesh Chandra, Pascal Démoulin, Tibor Török, Etienne Pariat, and Wahab Uddin. "Solar activity due to magnetic complexity of active regions." Proceedings of the International Astronomical Union 6, S273 (August 2010): 164–68. http://dx.doi.org/10.1017/s1743921311015183.

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AbstractActive regions (ARs), involved in the Halloween events during October-November 2003, were the source of unusual activity during the following solar rotation. The flares on 18-20 November 2003 that occur in the AR NOAA10501 were accompanied by coronal mass ejections associated to some particularly geoeffective magnetic clouds.Our analysis of the magnetic flux and helicity injection revealed that a new emerging bipole and consequent shearing motions continuously energized the region during its disk passage. The stored energy was eventually released through the interaction of the various systems of magnetic loops by several magnetic reconnection events. Active events on November 18 (filament eruptions and CMEs) were originated by shearing motions along a section of the filament channel that injected magnetic helicity with sign opposite to that of the AR. Two homologous flares, that occurred on November 20, were apparently triggered by different mechanisms as inferred from the flare ribbons evolution (filament eruption and CMEs). We studied in detail the behaviour of two North-South oriented filaments on November 20 2003. They merged and split following a process suggestive of ‘sling-shot’ reconnection between two coronal flux ropes. We successfully tested this scenario in a 3D MHD simulation that is presented in this paper.

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Journal articles on the topic 'Flame filament'

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