Impact of adhesive ingredients on adhesion between rubber and brass-plated steel wire in tire

Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of Cu_XS layer depth on rubber-metal adhesion. The depth profile of the Cu_XS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of Cu_XS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously.     

A waveform concatenation technique for text-to-speech synthesis

Designing text-to-speech systems capable of producing natural sounding speech segments in different Indian languages is a challenging and ongoing problem. Due to the large number of possible pronunciations in different Indian languages, a number of speech segments are needed to be stored in the speech database while a concatenative speech synthesis technique is used to achieve highly natural speech segments. However, the large speech database size makes it unusable for small hand held devices or human computer interactive systems with limited storage resources. In this paper, we proposed a fraction-based waveform concatenation technique to produce intelligible speech segments from a small footprint speech database. The results of all the experiments performed shows the effectiveness of the proposed technique in producing intelligible speech segments in different Indian languages even with very less storage and computation overhead compared to the existing syllable-based technique.     

Analyzing collective behavior from blogs using swarm intelligence

With the rapid growth of the availability and popularity of interpersonal and behavior-rich resources such as blogs and other social media avenues, emerging opportunities and challenges arise as people now can, and do, actively use computational intelligence to seek out and understand the opinions of others. The study of collective behavior of individuals has implications to business intelligence, predictive analytics, customer relationship management, and examining online collective action as manifested by various flash mobs, the Arab Spring (2011) and other such events. In this article, we introduce a nature-inspired theory to model collective behavior from the observed data on blogs using swarm intelligence, where the goal is to accurately model and predict the future behavior of a large population after observing their interactions during a training phase. Specifically, an ant colony optimization model is trained with behavioral trend from the blog data and is tested over real-world blogs. Promising results were obtained in trend prediction using ant colony based pheromone classier and CHI statistical measure. We provide empirical guidelines for selecting suitable parameters for the model, conclude with interesting observations, and envision future research directions.     

On the Role of C Addition on α Precipitation in a β Titanium Alloy

The onset of α nucleation in a carbon containing β-titanium alloy has been investigated by coupling atom probe tomography (APT) with transmission electron microscopy. The analysis of the APT results indicates that in addition to ω precipitates that can act as potential α nucleation sites, carbon atoms tend to form clusters within the β-matrix, which in turn give rise to additional nucleation sites for α, resulting in finer scale α precipitates due to increased nucleation density.     

Synthetic Applications of Carbohydrate-derived Donor-Acceptor Cyclopropanes

In this account, we elaborate our group's contribution towards understanding the chemistry of carbohydrate-derived donor-acceptor (DA) cyclopropanes. Our work was mainly focused on the ring opening of these versatile chiral synthons under the influence of Lewis acid promoters like electrophilic halogen species, TMSOTf, BF₃.OEt₂, etc. We studied various modes of ring opening on these DA cyclopropanes, envisaging the access to intriguing molecular architectures. These modes of reaction of the DA cyclopropanes can be controlled by strategically introducing an electron-withdrawing group (EWG) onto the cyclopropane ring, which could direct the ring cleavage by polarizing the cyclopropane C−C bond. Our studies also revealed that the ring opening is sluggish in the absence of an EWG. Using this concept, we demonstrated the synthesis of various biologically interesting molecular skeletons, viz., glycoamino acids (GAA), GAA nucleotides, α-levoglucosan amino acid, and septano-oligosaccharides, with high selectivity. We also applied our understanding to the first stereoselective synthesis of (S)-(−)-longianone and confirmed its absolute configuration. Apart from the inherently activated DA cyclopropanes, we introduced the in situ generation of DA cyclopropanes, starting from vinylcyclopropanes (VCPs). The ring-opening and ring-expansion chemistry of these easily accessible synthons was studied. The chemistry developed for carbohydrate-fused cyclopropanes was also applied for carbohydrate-derived spiro-cyclopropanes. The Lewis-acid-mediated ring opening of spiro-DA-cyclopropanes enabled easy access to fused furopyrans and spirolactones.     

Experimental and theoretical investigations of the adhesion time of Penicillium spores to cedar wood surface

In this study, the adhesion of 4 Penicillium strains (Penicillium granulatum, Penicillium crustosum, Penicillium commune and Penicillium chrysogenum) on cedar wood was examined qualitatively and quantitatively by using the extended DLVO (XDLVO) approach and the environmental scanning electronic microscopy (ESEM) technique. A comparison between the XDLVO theories and the ESEM technique was also investigated. The adhesion tests revealed that P. chrysogenum was not able to adhere on the cedar wood substrata, as predicted by the XDLVO approach. We have also found by ESEM that the three Penicillium strains (P. granulatum, P. crustosum, P. commune) adhered on wood, as not predicted theoretically.Moreover, the time of adhesion (3 h and 24 h) was used not only to compare the capacity of adhesion according to contact time but also to explain the discrepancies between the XDLVO approach prediction and the adhesion experiments. A positive relationship between the XDLVO approach and adhesion experiments has been observed after 3 h of adhesion. In contrast, a contradiction between the XDLVO predictions and the adhesion test results has been noted after 24 h of adhesion of Penicillium strains to the wood surface.     

A Study on the Impact of the Adhesion of Penicillium expansum on the Physicochemical Surface Properties of Cedar Wood

The sessile drop technique was used to investigate the evolution of the physicochemical properties of cedar wood as a function of contact time with the Penicillium expansum spores. The most important finding showed that the impact of different contact periods (2, 4, 6, 8, 10, and 24 hr) on the wood surface were very indicative. In fact, after 2 hr of contact, the results have shown a significant impact of the bioadhesion of spores to the substrate on both the hydrophobic character (θ_W = 108.5°; ΔGiwi = ?28.25 mJ/m²), the electron donor (γ^? = 13.63 mJ/m²), and the electron acceptor (γ⁺ = 4.35 mJ/m²) parameters that were significantly reduced compared to the initial wood (θ_W = 118.5°; ΔGiwi = ?6.29 mJ/m²; γ^? = 32.1 mJ/m²; and γ⁺ = 9.1 mJ/m²). In addition, this decrease of parameters continued over time to stabilize after 10 hr of contact. Indeed, after 24 hr, the acid/base properties were almost zero and the contact angle with water decreased to 30°. Moreover, it was found that the coefficient of correlation (r²) was strong between the contact angle with water, the surface energy, and the electron acceptor character with the contact time parameter with values (r² = 0.65), (r² = 0.79), and (r² = 0.68), respectively.     

Performance Analysis of Ferroelectric GAA MOSFET with Metal Grain Work Function Variability

Silicon - This work represents a unique GAA MOSFET with metal work-function variations (WFVs) and ferroelectric material as dielectric. A random distribution of metal grain (TiN) with grain size...     

Cassava starch‐graft‐polymethacrylamide copolymers as flocculants and textile sizing agents

Cassava starch‐graft‐polymethacrylamide (PMAM) copolymers were synthesized by a free‐radical‐initiated polymerization reaction, and the products were tested for their efficiency as flocculants and textile sizing agents. The highest percentages of grafting and monomer conversion were 79.9 and 78.0%, respectively. The grafted starches were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction analysis, scanning electron microscopy, differential scanning calorimetry, and thermogravimetric analysis. The average molecular weight of PMAM chains in the grafted starches ranged from 15.9 to 30.8 × 10⁵ g/mol. The grafted starches exhibited a higher peak viscosity and paste stability in comparison to the native starch (NS). Dynamic mechanical analysis showed that grafting provided fairly shear‐stable hydrogels, and the highest storage modulus obtained was 17,900 Pa compared to 1879 Pa for NS. The flocculation studies demonstrated the superiority of starch‐g‐PMAM over cassava starch and PMAM as an efficient flocculant. The tensile strength of cotton yarns sized with the starch‐grafted copolymer was significantly higher (104 MPa) compared to that sized with NS (34 MPa). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39810.