This study of five native speakers Korean investigates the role universals in their acquisition English obstruent voicing contrasts. The data were gathered from a passage and word list containing voiced voiceless obstruents initial, medial, final positions. Results reflected principles markedness L1 adult natural languages, suggesting that interlanguage systems behave according to languages.

Polycarbonate (PC) is a highly recyclable thermoplastic with high impact strength that bodes well to re-melting extrusion and shredding for positive environmental impact. For the goal of improving further, layered carbon fiber (CF) reinforcement has been added between PC sheets by hot pressing at 6.0 MPa 537 K 8 min. An addition cross-weave CF layer increased Charpy value, auc untreated [PC]4[CF]3 composite over resin reported all accumulative probabilities, Pf. At medial-Pf 0.50, was 3.13...

Acoustic emission (AE) and scanning electron microscope (SEM) techniques have been coupled with mechanical deformation to study the damage fracture mechanisms in a short fiber BMC composite. During tensile initial process observed SEM was formation of small cracks at filler particles glass fibers. Damage due this mechanism identified acoustic 40 dB ampli tude range. Onset occurred very low strains con tinued accumulate until fracture. At higher were coalesce form large spanned by pulled-out...

Compression-molded short-fiber GFRP-BMC panels have random distribution of solidification texture angles from zero to 90 degrees in the center mother panels. Hence, there is significantly lower impact strength panel than outside. However, experimental results showed homogeneous low voltage electron beam irradiation (HLEBI) applied region apparently enhances Charpy values (auc) 5 25%. Fracture mechanism was observed convert at auc > ∼5.4–6.7 kJ·m−2 clean secondary microcrack proliferation...

Experimental results showed homogeneous 100 keV-class low voltage electron beam irradiation (HLEBI) prior to lamination assembly (our new method) often improved the Charpy impact values (auc) of sandwich structural CFRP/ABS/CFRP (carbon fiber reinforced epoxy polymer) and (acrylonitrile butadiene styrene) with volume fraction carbon fibers for cost reduction safety. The auc at each Pf laminated by both high-strength light CFRP plies ABS core separately irradiated from 0.04 0.30 MGy-HLEBI...

Electrical conductivity (σ) enhancement, control, aging stability, and linear relation between σ reciprocal temperature (1/T) in PTFE (Teflon) had been examined by homogeneous low potential electron beam irradiation (HLEBI). Irradiations up to 0.432 MGy were found raise the of more than two orders magnitude. In addition, control movement or Fermi level HLEBI on polymers seems possible since at levels 0.216 MGy, a strong dependence was observed. Aging stability investigation showed saturated...

Bird strike, volcanic rock, hailstones, micrometeoroids, or space debris can cause damage to aircraft and vehicles, therefore their composite materials must have high impact resistance maximize safety. In a 55% wt. CaCO3 compression molded short glass fiber polyester GFRP-BMC (bulk compound), shortening the nominal 6.4 mm length formulation, by 30 min extended mixing, 0.44 was found increase Charpy values, auc, without change in molding equipment. Specimens were cut from square panels spiral...

Effects of short fiber with sub-millimeter length on tensile strain, εf and strength, σf were investigated for a bulk molding compound (BMC) glass reinforced polymer (GFRP) composite 20 mass% E-short fibers. The values BMC-GFRP samples 0.44 mm fibers almost 40 60% higher than that long (3.2 6.4 in length), as well more 65 110% the filled free resin, respectively. reduced fracture strain (εf⁄εf,6.4) strength (σf⁄σf,6.4) function end density, ρE (cm−3) expressed by following equations linear...

The purpose of this study is to investigate a lighter, cheaper and possibly stronger alternative CFRP, by obtaining the Charpy impact values (auc) sandwich structural composite (CFRP/PC/CFRP) constructed polycarbonate (PC) core between two thin plies carbon cross textile fiber/epoxy (CFRP) within temperature range aircraft operation, from 200 403 K below glass transition PC (Tg = 422 K). auc CFRP/PC/CFRP were compared with 2.0 mm thick 12-ply CFRP laminate. Results showed overall, had higher...

Effects of tensile prestress level on Charpy impact value (auc) 50 vol% continuous unidirectional 0 degree oriented carbon fiber reinforced epoxy polymer (CFRP) were investigated. Experimental results showed the auc at mid-fracture probability Pf = 0.50 induced by a large 17.6 MPa (109 kJm−2) was increased 30% over that (84 slight 0.25 MPa. The statistically lowest as calculated 3-parameter Weibull equation raised 26% from 73 to 92 kJm−2 showing reliability part strength. Fracture surface...

Impact by hailstone, volcanic rock, bird strike, or also dropping tools can cause damage to aircraft materials. For maximum safety, the goal is increase Charpy impact strength (auc) of a carbon-fiber-reinforced thermoplastic polyphenylene sulfide polymer (CFRTP-PPS) composite for potential application commercial parts. The layup was three cross-weave CF plies alternating between four PPS plies, [PPS-CF-PPS-CF-PPS-CF-PPS], designated [PPS]4[CF]3. To strengthen, new process CFRP-PPS employed...

In short-carbon-fiber-reinforced polyamide 66 articles shaped by 3D printing (3D-SCFRPA66), the interfaces between printed layers are often susceptible to damage, and composite is excessively brittle. Therefore, a novel treatment for 3D-printed (3D-SCFRPA66) using homogeneous low-potential electron beam irradiation (HLEBI) enhance tensile properties was investigated. 3D-SCFRPA66 samples, ductility measured based on following parameters: strain at strength (corresponding deformation) (εts)...

It is a serious problem that short carbon fiber reinforced polyamide 66 (SCFRPA66) cannot be easily shaped by 3D-printing for practical usages. In order to improve on the brittleness, homogeneous low potential electron beam irradiation (HLEBI) both sides of 3D-SCFRPA66 samples was found increase strain at tensile strength (εts), corresponding deformation and fracture (εf), as well resistant energy (Ehd), whereas HLEBI decreased (σts). This improvement in ductility can explained lone pair...

Adhesive 2-layer lamination joint of aluminum/carbon fiber reinforced epoxy polymer (Al/CFRP) were prepared by a new adhesion method, double-step treatment consisting applying low dose (= 0.22 MGy) homogeneous energy electron beam irradiation (HLEBI) to the CFRP and Al prior assembly hot-press in vacuum below 1 Pa for 2 h at 403 K. No fasteners or external adhesives applied: cured enhanced HLEBI acts as adhesive Al. The apparently boosted shear strength (τ) Al/CFRP 45% probability (Ps =...

A new method with extremely large friction force taking advantage of the high interface area carbon fiber (CF: 6 µm-diameter) cross weave cloth, surface activated by homogeneous low voltage electron beam irradiation (HLEBI) on ABS half-length prior to dipping in resin enhance ability difficult adhere thermoplastic CF has been suggested for a joint (Ti/EBCF/ABS) reinforced polymer and titanium (Ti). The was strengthened HLEBI over that without HLEBI. Experimental results showed ultimate...

Adhesive 2-layer lamination joints of polyethylene terephthalate (PET)/epoxy resin were prepared without the use hot press using a new adhesion method applying homogeneous low energy electron beam irradiation (HLEBI) to PET prior assembly by hand pressure. HLEBI treatment within range 0.13 0.43 MGy increased adhesive force peeling (oFp) substantially over untreated. The largest oFp values at optimal dose 0.30 12.4, 37.2 and 190 Nm−1, which more than 2.2, 2.8 9.5 times larger 5.76, 13.5 20.0...

A nickel coated carbon fiber reinforced joint (Ti/NiCF/CFRP) was suggested and developed between epoxy polymer (CFRP) titanium (Ti). The most important point of the new method are not only extremely large friction force by broad interface with 6 µm-diameter, but also Ni-coating for suppression TiC formation enhancement contact ability wrapped molten Ti. part strengthened impregnated nickel-coated (NiCF) exhibited high Charpy impact value (auc). Since carefulness aircraft parts would be...

A new titanium (Ti)/polycarbonate (PC) joint [Ti/EBCF/PC] internally connected by homogeneous low potential electron beam irradiation (HLEBI) activated cross-weave carbon fiber (6 μm in diameter) cloth insert taking advantage of broad CF surface area had been developed. Applying HLEBI dose the range 0.043 to 0.43 MGy bare half-length prior dipping thermoplastic PC molten resin enhanced ultimate tensile strength (σb) Ti/EBCF/PC over that without [Ti/CF/PC]. The 0.30 appeared be near optimum...

Adhesive 2-layer lamination joints of 18 mass%Cr-8 mass%Ni austenite stainless steel and carbon fiber reinforced polymer (18-8/CFRP joint) were prepared using a new adhesion method consisting applying low dose 0.13 MGy homogeneous energy electron beam irradiation (HLEBI) to connecting surfaces the 18-8 CFRP prior assembly hot-pressing in vacuum below 1 Pa for 2 h at 401 ± 0.5 K. Although untreated 18-8/CFRP joint exhibited decent by hot-pressing, application HLEBI apparently improved tensile...

A new process of internal activation glass fiber reinforced thermoplastic polymer (GFRTP) Polypropylene (PP) was achieved by homogeneous low energy electron beam irradiation (HLEBI) to the interlayered chopped strand mats (GF-CSM) prior assembly. Panels were fabricated hot-press consisting 5 HELBI-treated GF-CSMs between 6 untreated PP sheets. HLEBI improved Charpy impact value (auc) internally activated GFRTP. from 0.22 0.86 MGy mostly auc at each accumulative probability fracture (Pf)....

In short carbon fiber reinforced polyetheretherketone (SCFRP-PEEK) composites, fibers and PEEK matrix typically exhibit a weak adhesive force at the interface. However, applying 0.43 MGy dose of homogeneous low-voltage electron beam irradiation (HLEBI) was apparently shown to improve not only bending modulus (Ef) 65.5% median-ranked cumulative probability evaluated as distribution function (PE = 0.50) from 6.7 11.1 GPa, but also Charpy impact fracture value (auc) 17.5% (Pf 16.6 19.5 kJ m−2....

In a highly CaCO3 filled compression molded short glass fiber polyester GFRP-BMC composite with high solidification texture angle of 71 ± ∼7 deg respect to specimen length, Charpy impact strength, auc at both low −79°C (194 K) and 70°C (343 temperatures were apparently increased 69 32%, respectively over that RT (293 K). This result was unexpected. Test beyond presently accepted extreme operating temperature range commercial air flight −62°C (211 53°C (326 As expected, optical observation...

Up to now, increasing modulus of fiber reinforced polymers (FRPs) by shortening fibers has not been reported however, length from commercial 6.4 0.44 mm additional mixing paste prior injection molding was found increase initial and maximum tensile 5 25% in a 3-phase system highly CaCO3 filled 20 mass% E-glass thermoset polyester/styrene-butadiene polymer bulk-molding compound (GFRP-BMC). The increased number spaces between appears allow for action coefficient thermal expansion (CTE)...

Experimental results show applying homogeneous low-energy electron beam irradiation (HLEBI) treatment of 0.30 MGy to both sides sandwich structural CFRP/ABS/CFRP composite constructed an ABS core between two thin plies carbon cross textile fiber/epoxy CFRP apparently increased Charpy impact values, auc at all fracture probabilities, Pf temperatures 77, 200 and 300 K, within the low temperature range aircraft operation below minimum reusable launch vehicle in space reported as 116 K. At...