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991.
992.
Ennouri Triki Carlos Arrieta Hychem Boukehili Toan Vu‐Khanh 《Polymer Composites》2012,33(6):1007-1017
In this article, a new method to characterize the tear behavior of coated textiles using fracture mechanics is proposed. The energy dissipated in tearing (EDT) of as‐received and thermally aged samples of polyester fabric, polyvinyl acetate rubber coating, and textile‐coating composites was calculated and compared. The EDT of the coated fabric displayed a slightly smaller value than the fabric alone, whereas the EDT of the coating was found to be negligible when compared with the other two. The presence of the coating is believed to have a detrimental effect on the tearing behavior of the coated fabric as it hinders interfilament slippage. A master curve of EDT retention vs. aging time for noncoated and coated fabric samples was constructed using the time–temperature superposition principle and fitted using the Hill equation. Fourier transform infrared analyses carried out on aged fabric samples hinted at a possible chain scission process, whereas the crystallinity of fabric samples, calculated via differential scanning calorimetry, was found to decrease after thermal aging. Scanning electron microscopy images revealed an increase in surface roughness after aging that may reduce interfilament friction. These results, coupled to an increase in the adhesion strength between fabric and coating, are likely the cause of the reduction of EDT noticed in aged coated and noncoated fabrics compared with as‐received ones. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers 相似文献
993.
Ennouri Triki Phuong Nguyen‐Tri Hychem Boukehili Toan Vu‐Khanh 《Polymer Composites》2012,33(9):1578-1585
Tearing resistance is an important parameter for evaluating the reliability of textile structures, especially in the case of protective materials. In order to better understand the individual contribution of the different mechanisms involved in the tearing process, a study of the relation between the fabric and yarn properties characterizing these mechanisms and the tearing energy has been carried out. For that purpose, polyester fabrics with two types of weave patterns and various values of filling yarn density and linear density were characterized in terms of tongue tear energy, yarn and fabric modulus, breaking force and elongation at break, yarn slippage, and yarn jamming. Data for all tested fabrics relied on a unique master curve when the tearing energy was expressed as a function of the transverse yarn slippage force. This demonstrates the strong contribution of transverse yarn slippage to the tearing process, a mechanism which has generally been overlooked in previous works on tearing. Relationships between the tearing energy and the other properties characteristics of the mechanisms involved in tearing of woven textiles were also observed. These results build the path toward the development of models for the tearing energy of textile structures. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers 相似文献
994.
Katarina Ohlsson Tina Bergman Per-Erik Sundell Tomas Deltin Irina Tran Martin Svensson Mats Johansson 《Progress in Organic Coatings》2012
Limitation of volatile organic compound (VOC) emissions has lead to the development of new coil coating systems with reduced solvent content. Reactive diluents derived from vegetable oils have been used to substitute up to 40% of the white spirit. The use of vegetable oil derivatives further reduces the handling of solvents improving the workplace environment and safety, enhances the film properties, and introduces a renewable resource in the final coating. The concept can be described as a melamine crosslinkable alkyd which is formed in parallel to the crosslinking process. 相似文献
995.
Techno-economic analysis of potential natural gas liquid (NGL) recovery processes under variations of feed compositions 总被引:1,自引:0,他引:1
Mesfin Getu Shuhaimi Mahadzir Nguyen Van Duc Long Moonyong Lee 《Chemical Engineering Research and Design》2013
This paper presents the different process schemes used for known NGL recovery methods with respect to their economic performance. The original turbo-expander (ISS) was considered as base case plant. The GSP, CRR and RSV process schemes focus on improvement at the top of the demethanizer column. The IPSI-1 and IPSI-2 schemes focus on the bottom of the demethanizer column. All the process schemes were initially built using Aspen HYSYS with a common set of operating criteria. Numerous simulation runs were made by taking various typical feed compositions classified as lean and rich. The economic assessment for each process scheme was later made by considering the capital cost, operating cost and profitability analysis. Results showed that the IPSI-1 process scheme gives the best economic performance with lowest TAC and payback time compared to the other process schemes. On the other hand, the RSV process gives higher TAC and payback time compared to others. 相似文献
996.
Khanh-Quang Tran Magnus Hagström John G. Korsgren Britt-Marie Steenari Oliver Lindqvist Jan B. C. Pettersson 《Aerosol science and technology》2013,47(10):955-962
A novel particle trap impactor has been developed for use with the gas-quenching probe in order to exclude solid particles from entering into the probe during sampling of gaseous metallic species in fluidized bed combustion conditions. The impactor must be small in size (Øimpactor ≤ Øprobe = 45 mm) but capable of collecting a relatively large amount of particles at elevated temperatures. As the first step, the impactor was designed, constructed, and tested at room temperature for KCI aerosol particles. The impactor with a nozzle of 0.95 mm in diameter, in combination with the orifice-to-jet diameter ratio of 1.5 and the ratio of the jet-to-plate spacing to jet diameter at 1.4 yielded a sharp cutoff curve with a maximum collection efficiency of about 0.9 and a √Stk50 value of about 0.22. In addition, the collection efficiency of the impactor was compared with the particle removal efficiency of a filter of the same type as the filter previously used with the gas-quenching probe. The difference from the comparison is very small, indicating that the impactor can be used to replace the filter to prevent fly ash particles from entering the gas-quenching probe in fluidized bed combustion conditions. 相似文献
997.
Tran Thi Thu Hien Takashi Shirai Masayoshi Fuji 《Journal of the American Ceramic Society》2013,96(12):3708-3711
An amorphous silica powder was subjected to mechanical and hydrothermal treatment. Silanol surface groups, which play an active role in the chemical modification of silica, were produced by these two treatments. The surface activity of raw and treated powders was measured as the amount of dissolved Si4+ ion in ammonia (NH3) and potassium hydroxide (KOH) solutions at different concentrations. KOH solution was more effective than NH3 solution in activating the surface of the silica powder. Nonfiring glass was successfully fabricated using mechanochemically treated silica powder. Glass properties such as morphology and transparency were analyzed using scanning electron microscope and UV–vis–NIR techniques. Possible reaction mechanisms of powder surface activation occurring during hydrothermal and condensation processes are also discussed. 相似文献
998.
Thierry Tran Byoung‐Ho Lee Han‐Seung Yang Sunee Chotineeranat Klanarong Sriroth Hyun‐Joong Kim 《Starch - St?rke》2011,63(10):637-648
The feasibility and industrial potential of using bio‐flours from tropical crop residues, in particular starch containing bio‐flours, for the manufacture of bio‐composites was investigated. Polypropylene (PP) and poly(butylene succinate) (PBS) were compounded with bio‐flours from pineapple skin (P) and from non‐destarched (CS) and destarched (C) cassava root by twin‐screw extrusion. In CS composites, two levels of starch granules melting were achieved by adjusting the extrusion temperature, enabling control of morphological and mechanical properties. The use of bio‐flours reduced tensile strength by 26–48% and impact strength by 14–40% when the proportion of bio‐flour was increased to 40% w/w, while flexural strength initially increased upon addition of bio‐flours, before decreasing at higher loads. The use of compatibilizers, in particular maleic anhydride‐polypropylene (MAPP) in PP composites with 30% bio‐flour resulted in tensile strength similar to non‐compatibilized composites with 10% bio‐flour (34–35 MPa). MAPP also increased flexural strength to higher levels than pure PP, resulting in a stronger, but less flexible material. 相似文献
999.
Supatcharee Siriwong Wannaporn Thepbandit Nguyen Huy Hoang Narendra Kumar Papathoti Karsidete Teeranitayatarn Tippawun Saardngen Kanjana Thumanu Sundaresan Bhavaniramya Vaseeharan Baskaralingam Toan Le Thanh Piyaporn Phansak Natthiya Buensanteai 《International journal of molecular sciences》2021,22(15)
This study focuses on a commercial plant elicitor based on chitooligosaccharides (BIG®), which aids in rice plant growth and disease resistance to bacterial leaf blight (BLB). When the pathogen (Xoo) vigorously attacks rice that has suffered yield losses, it can cause damage in up to 20% of the plant. Furthermore, Xoo is a seed-borne pathogen that can survive in rice seeds for an extended period. In this study, when rice seeds were soaked and sprayed with BIG®, there was a significant increase in shoot and root length, as well as plant biomass. Furthermore, BIG®-treated rice plants showed a significant reduction in BLB severity of more than 33%. Synchrotron radiation-based Fourier transform infrared (SR-FTIR) analysis was used to characterize BIG®’s mechanism in the chemical structure of rice leaves. The SR-FTIR results at 1650, 1735, and 1114 cm−1 indicated changes in biochemical components such as pectins, lignins, proteins, and celluloses. These findings demonstrated that commercial BIG® not only increased rice growth but also induced resistance to BLB. The drug’s target enzyme, Xoo 1075 from Xanthomonas oryzae (PDB ID: 5CY8), was analyzed for its interactions with polymer ingredients, specifically chitooligosaccharides, to gain molecular insights down to the atomic level. The results are intriguing, with a strong binding of the chitooligosaccharide polymer with the drug target, revealing 10 hydrogen bonds between the protein and polymer. Overall, the computational analysis supported the experimentally demonstrated strong binding of chitooligosaccharides to the drug target. 相似文献
1000.
We demonstrate, by partial experiment and simulation, a re-modulation scheme of the lightwave carrier imbedded in a downstream
optical signals under differential quadrature phase shift keying (DQPSK) modulation format for upstream transmission over
passive optical networks (PONs) at a bit rate of 100 Gb/s. The recovery of the optical carrier with the precise wavelength
is implemented using an injection laser incorporating an optical phase locked loop (OPLL). In the computer simulation, the
OPLL is implemented by a Simulink model consisting of interconnected system blocks following exactly the physical phenomena
of the hardware structures. This model is then integrated with DQPSK modulation formats for up- and down-transmissions in
PONs. Pulse shaping of Non-Return-to-Zero and Return-to-Zero (RZ) of 50% duty cycle and 67% duty cycle are used, respectively.
Dispersion tolerance of 25 ps/nm with a bit error rate (BER) of 10−9 is achieved for both down- and upstream transmissions over fully dispersion compensated 80- km standard SMF and 1.5- km SSMF
equivalent dispersion with carrier suppressed RZ pulse shaping (CS-RZ 67%). The contribution to BER by the timing synchronization
error at the sampling of the optical network unit for re-modulation and related power penalty of these modulation formats
is also investigated. It is noted that using the optical phase locking technique it is possible to remove any cross talks
which may be generated from nonlinear effects such as cross-phase modulation, self-phase modulation, and four wave mixing. 相似文献